WorldWideScience

Sample records for mev ecis computer

  1. The NASTRAN Error Correction Information System (ECIS)

    Science.gov (United States)

    Rosser, D. C., Jr.; Rogers, J. L., Jr.

    1975-01-01

    A data management procedure, called Error Correction Information System (ECIS), is described. The purpose of this system is to implement the rapid transmittal of error information between the NASTRAN Systems Management Office (NSMO) and the NASTRAN user community. The features of ECIS and its operational status are summarized. The mode of operation for ECIS is compared to the previous error correction procedures. It is shown how the user community can have access to error information much more rapidly when using ECIS. Flow charts and time tables characterize the convenience and time saving features of ECIS.

  2. ECi/ECiQ和AxSYM全自动免疫系统的性能比较%Laboratory evaluation of the Eci/ECiQ and AxSYM automatic immunoassay system for detection of HBsAg and anti-hepatitis C virus

    Institute of Scientific and Technical Information of China (English)

    曾争; 于敏; 张乃临; 公维波

    2007-01-01

    目的:比较ECi/ECiQ和AxSYM系统对样品检测的重复性、气泡检出率及线性范围,讨论其对临床检测结果的影响.方法:HBsAg/抗-HCV强阳性样品各20份,正常人血清标本中分别加入一定比例的上述样品至S/Co比值在阈值(Cut-Off)并重复检测40次作重复性实验;气泡检出试验是在样品中加入50μL气体并重复检测20次;正常人血清连续系列稀释HBsAg强阳性标本并检测线性范围试验.结果:ECi/ECiQ和AxSYM系统HB sAg重复性(CV%)各为3.57%和3.87%;ECi/ECiQ和AxSYM系统抗-HCV各为5.05%和17.01%.ECi/ECiQ和AxSYM系统HBsAg气泡检出率各为100%和55%;ECi/ECiQ和AxSYM系统抗-HCV各为35%和15%.ECi/ECiQ系统和AxSYM系统HBsAg均未出现假阴性;ECi/ECiQ系统抗-HCV未出现假阴性,而AxSYM系统为70.6%.ECi/ECQ在稀释1∶40000时仍阳性,其线性相关系数为0.9957,而AxSYM系统在稀释1∶10000时阳性,其线性相关系数为0.9384.结论:ECi/ECiQ和AxSYM两系统均适用于临床检测,但ECi/ECiQ系统对整个检测流程质量控制要求高,而AxSYM系统对样品的质量要求相对较低,在低值标本检测中容易造成假阴性,ECi/ECiQ系统的敏感性和重复性比AxSYM系统好.

  3. Twenty Years of the European Information Systems Academy at ECIS

    DEFF Research Database (Denmark)

    Stein, Mari-Klara; Galliers, Robert D.; Whitley, Edgar A.

    2016-01-01

    While the information systems (IS) community is increasingly international, it is reasonable to expect that different regions might display different research approaches, interests and publication orientations. This paper contributes to the growing number of historical accounts in the IS field...... by further developing the profile of European IS research that was reported on in EJIS following the first 10 years of the European Conference on Information Systems (ECIS). On the basis of an analysis of all papers published in ECIS proceedings during the 10-year period 2003–2012, the paper highlights three...... these observed characteristics within broader historical and contextual features such as the changing European academic landscape, with increasing pressures to ‘publish or perish’ in order to be internationally competitive. Our contribution lies in providing a contemporaneous account of the dominant contextual...

  4. An approach to collective behavior in cell cultures: modeling and analysis of ECIS data

    Science.gov (United States)

    Rabson, David; Lafalce, Evan; Lovelady, Douglas; Lo, Chun-Min

    2011-03-01

    We review recent results in which statistical measures of noise in ECIS data distinguished healthy cell cultures from cancerous or poisoned ones: after subtracting the ``signal,'' the 1 /fα noise in the healthy cultures shows longer short-time and long-time correlations. We discuss application of an artificial neural network to detect the cancer signal, and we demonstrate a computational model of cell-cell communication that produces signals similar to those of the experimental data. The simulation is based on the q -state Potts model with inspiration from the Bak-Tang-Wiesenfeld sand-pile model. We view the level of organization larger than cells but smaller than organs or tissues as a kind of ``mesoscopic'' biological physics, in which few-body interactions dominate, and the experiments and computational model as ways of exploring this regime.

  5. Implementation of the networked computer based control system for PEFP 100MeV proton linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Song, Young Gi; Kwon, Hyeok Jung; Jang, Ji Ho; Cho, Yong Sub [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    The 100MeV Radio Frequency (RF) linac for the pulsed proton source is under development in KAERI. The main systems of the linac, such as the general timing control, the high power RF system, the control system of klystrons, the power supply system of magnets, the vacuum subsystem, and the cooling system, should be integrated into the control system of PEFP. Various subsystems units of the linac are to be made by other manufacturers with different standards. The technical integration will be based upon Experimental Physics and Industrial Control System (EPICS) software framework. The network attached computers, such as workstation, server, VME, and embedded system, will be applied as control devices. This paper is discussed on integration and implementation of the distributed control systems using networked computer systems.

  6. Coupled-channel analysis for 20.4 MeV energy of p-^{64}Zn inelastic scattering

    Indian Academy of Sciences (India)

    Harun Yücel; Müşfik Taşan

    2012-02-01

    In this study, a coupled-channel (CC) analysis of the elastic and the inelastic scattering of 20.4 MeV polarized protons from a 64Zn target leading to the deformed 2+, $3^−$, $2^+_2$ states was performed. The CC potential parameters and the deformation parameters of the excited states corresponding to the best fit to the experimental differential cross-sections and the analysing powers data were determined. For $2^+_2$ excited state, a mixed type was used and a good fit to the data was provided. The CC calculation results were compared to the pure distorted wave Born approximation (DWBA) calculation results which were calculated using the new parameters. All calculations were conducted using the computer code ECIS06.

  7. PWAS EMIS-ECIS Active Carbon Filter Residual Life Estimation Methodology

    Science.gov (United States)

    2013-09-23

    can detect the presence of contaminants, such as water and kerosene in the carbon bed 5. EMIS and ECIS measurements are consistent with each other...1. Flow rate F 2. Start time t0 Run carbon bed exhaust through H2O2 solution with methyl red indicator Record: The time when the indicator

  8. Design rule for optimization of microelectrodes used in electric cell-substrate impedance sensing (ECIS).

    Science.gov (United States)

    Price, Dorielle T; Rahman, Abdur Rub Abdur; Bhansali, Shekhar

    2009-03-15

    This paper presents an experimentally derived design rule for optimization of microelectrodes used in electric cell-substrate impedance sensing (ECIS) up to 10MHz. The effect of change in electrode design (through electrode sensor area, lead trace widths, and passivation coating thickness) on electrode characteristics was experimentally evaluated using electrochemical impedance spectroscopy (EIS) measurements and analyzed using equivalent circuit models. A parasitic passivation coating impedance was successfully minimized by designing electrodes with either a thicker passivation layer or a smaller lead trace area. It was observed that the passivated lead trace area to passivation coating thickness ratio has a critical value of 5.5, under which the impedance contribution of the coating is minimized. The optimized design of ECIS-based microelectrode devices reported in this work will make it possible to probe the entire beta dispersion region of adherent biological cell layers by reducing measurement artifacts and improving the quality of data across the beta-dispersion region. The new design will enable the use of the commonly used ECIS technique to measure real-time cellular properties in high frequency ranges (beta dispersion) that was not possible thus far.

  9. Commercial Off-the-Shelf (COTS) Components and Enterprise Component Information System (eCIS)

    Energy Technology Data Exchange (ETDEWEB)

    John Minihan; Ed Schmidt; Greg Enserro; Melissa Thompson

    2008-06-30

    The purpose of the project was to develop the processes for using commercial off-the-shelf (COTS) parts for WR production and to put in place a system for implementing the data management tools required to disseminate, store, track procurement, and qualify vendors. Much of the effort was devoted to determining if the use of COTS parts was possible. A basic question: How does the Nuclear Weapons Complex (NWC) begin to use COTS in the weapon Stockpile Life Extension Programs with high reliability, affordability, while managing risk at acceptable levels? In FY00, it was determined that a certain weapon refurbishment program could not be accomplished without the use of COTS components. The elements driving the use of COTS components included decreased cost, greater availability, and shorter delivery time. Key factors that required implementation included identifying the best suppliers and components, defining life cycles and predictions of obsolescence, testing the feasibility of using COTS components with a test contractor to ensure capability, as well as quality and reliability, and implementing the data management tools required to disseminate, store, track procurement, and qualify vendors. The primary effort of this project then was to concentrate on the risks involved in the use of COTS and address the issues of part and vendor selection, procurement and acceptance processes, and qualification of the parts via part and sample testing. The Enterprise Component Information System (eCIS) was used to manage the information generated by the COTS process. eCIS is a common interface for both the design and production of NWC components and systems integrating information between SNL National Laboratory (SNL) and the Kansas City Plant (KCP). The implementation of COTS components utilizes eCIS from part selection through qualification release. All part related data is linked across an unclassified network for access by both SNL and KCP personnel. The system includes not

  10. Outcomes of stage IIB osteosarcoma treated by limb salvage surgery using extracorporeally irradiated (ECI autograft

    Directory of Open Access Journals (Sweden)

    Achmad F. Kamal

    2011-05-01

    Full Text Available Background: Extracorporeally irradiated (ECI technique is an alternative of limb salvage procedure in treating osteosarcoma regarding limitation of endoprosthesis and allograft. This study evaluated the outcomes of limb salvage surgery using extracorporeally irradiated (ECI autograft and its correlation with patient’s characteristics.Methods: Retrospective cohort design was performed to study 20 patients with stage IIB osteosarcoma treated by ECI autograft from 1995 to 2008. Survival, local recurrence, metastases, complications, union time and functional score based on Musculoskeletal Tumor Society scoring system-(MSTS were evaluated. Kaplan-Meier method was used to describe survival, local recurrence free survival, and metastases free survival. The correlation among patient’s characteristics that were age, gender, duration, site of tumor size, type of osteosarcoma, SAP (serum alkaline phosphatase level, type of biopsy, and type of Huvos were analyzed by Log rank test. Chi-square test was used to analyze the correlation between MSTS score and patient’s characteristics, local recurrence, metastases, complications.Results: Five-year survival was 54.97 ± 9.8 %, five-year local recurrence free survival was 66.5 ± 7.6%, and five year metastasis-free survival was 57.13 ± 10.04%. Six patients died, five were due to lung metastases and one due to complication of chemotherapy. Three underwent amputation after local recurrence. Kaplan-Meier curve showed that a good type of Huvos (III, IV always gave better survival, local recurrence free survival, and metastases free survival than poor type of Huvos (I,II. Normal SAP level gave better local recurrence free survival compare to increased level of SAP. Mean of union rate was 8.13 months. MSTS mean score was good (70.63% in patients with no evidence of disease. MSTS score was poor in patients with local recurrence (p = 0.025, metastases (p = 0.01, complications (p = 0.03, and the

  11. Impedimetric characterization of human blood using three-electrode based ECIS devices

    Directory of Open Access Journals (Sweden)

    Rangadhar Pradhan

    2012-07-01

    Full Text Available In this study, three-electrode based electric cell-substrate impedance sensing (ECIS devices were used to study the electrical properties of blood and its constituents using electrochemical impedance spectroscopy. The three-electrode based ECIS devices were fabricated using micromachining technology with varying sizes for working, reference, and counter electrodes.  The blood and its constituents such as serum, plasma, and red blood cells (RBCs were prepared by conventional methods and stored for impedance measurement using fabricated microdevices. Equivalent circuits for blood, serum, plasma, and RBCs were proposed using the software package ZSimpWin to validate the experimental data. The proposed equivalent circuit models of blood and its components have excellent agreement up to a frequency of 1 MHz.  It is evident from the experimental results that blood and its components have specific impedance signatures that decrease with the increase of frequency. Blood shows higher impedance than the other samples in the lower frequency range (<50 kHz.  It was also found that above 50 kHz, the impedance value of RBCs is nearly the same as whole blood. The impedance of serum and plasma steadily decreases with the increase of frequency up to 100 kHz and flattens out after that. The minimum impedance value achieved for serum and plasma is much less than the value obtained for whole blood.

  12. 75 FR 38179 - Proposed Collection; Comment Request for Forms W-8BEN, W-8ECI, W-8EXP, and W-8IMY

    Science.gov (United States)

    2010-07-01

    ... Internal Revenue Service Proposed Collection; Comment Request for Forms W-8BEN, W-8ECI, W- 8EXP, and W-8IMY... 104-13 (44 U.S.C. 3506(c)(2)(A)). Currently, the IRS is soliciting comments concerning Form W-8BEN, Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding, Form W-8ECI,...

  13. Child Developmental Impact of Pittsburgh's Early Childhood Initiative (ECI) in High-Risk Communities: First-Phase Authentic Evaluation Research.

    Science.gov (United States)

    Bagnato, Stephen J.; Suen, Hoi K.; Brickley, Dale; Smith-Jones, Janell; Dettore, Ernie

    2002-01-01

    This study used an "enhanced constructed comparison group" statistical model to conduct longitudinal research on the child developmental impact of Pittsburgh's early childhood initiative (ECI), a partnership to provide high-quality early care and education for children in high-risk neighborhoods. First-phase findings indicate that…

  14. A containment analysis for SBLOCA without ECI in the refurbished Wolsong-1 Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, T.M.; Moon, B.J.; Bae, C.J.; Lee, S.H.; Choi, C.J.; Lee, D.S. [NSSS, Korea Power Engineering Company, Inc., Daejeon (Korea, Republic of); Kim, S.M. [NETEC, Korea Hydro and Nuclear Power Company, Inc., Daejeon (Korea, Republic of)

    2010-07-01

    A small break leading to loss of coolant accident (SBLOCA), being one of the topic accidents in the nuclear plant diagnosis in recent years, has been analyzed and evaluated for the refurbished Wolsong-1 Nuclear Power Plant (NPP). The industry standard toolset (IST) codes developed by CANDU Owners Group and updated models including design change parameters are applied to the event analyses. GOTHIC code has been used for the containment analysis of Wolsong-1. Also, SMART-IST code fitted in the Iodine Chemistry (IMOD-2) model has been used to predict nuclide behavior within the containment considering various aspects. IMOD-2 was incorporated into SMART-IST as a module dealing the chemical transformations and mass transfer of iodine species in containment. IMOD-2 model is very sensitive to paint and chemicals. The parameter studies for IMOD-2 model are performed to decide the analysis value set. The developed methodology and the results of SBLOCA without ECI are presented herein. Under the most heat-up conditions, the radionuclide release from the failed fuel into the containment and subsequently to the environment is such that the radioactive doses to the public are below the acceptable limits. (author)

  15. ECI-4 screening of attention deficit-hyperactivity disorder and co-morbidity in Mexican preschool children: preliminary results Tamizaje del trastorno por déficit de atención-hiperactividad y su co-morbilidad en preescolares mexicanos por el ECI-4: resultados preliminares

    OpenAIRE

    2006-01-01

    OBJECTIVE: To examine prospectively usefulness of Early Childhood Inventory-4 (ECI-4) in identifying attention deficit-hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), and conduct disorder (CD). METHOD: A sample of children

  16. Online Measurement of Real-Time Cytotoxic Responses Induced by Multi-Component Matrices, such as Natural Products, through Electric Cell-Substrate Impedance Sensing (ECIS

    Directory of Open Access Journals (Sweden)

    Adyary Fallarero

    2015-11-01

    Full Text Available Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract’s pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow.

  17. Online Measurement of Real-Time Cytotoxic Responses Induced by Multi-Component Matrices, such as Natural Products, through Electric Cell-Substrate Impedance Sensing (ECIS).

    Science.gov (United States)

    Fallarero, Adyary; Batista-González, Ana E; Hiltunen, Anna K; Liimatainen, Jaana; Karonen, Maarit; Vuorela, Pia M

    2015-11-12

    Natural products are complex matrices of compounds that are prone to interfere with the label-dependent methods that are typically used for cytotoxicity screenings. Here, we developed a label-free Electric Cell-substrate Impedance Sensing (ECIS)-based cytotoxicity assay that can be applied in the assessment of the cytotoxicity of natural extracts. The conditions to measure the impedance using ECIS were first optimized in mice immortalized hypothalamic neurons GT1-7 cells. The performance of four natural extracts when tested using three conventional cytotoxicity assays in GT1-7 cells, was studied. Betula pendula (silver birch tree) was found to interfere with all of the cytotoxicity assays in which labels were applied. The silver birch extract was also proven to be cytotoxic and, thus, served as a proof-of-concept for the use of ECIS. The extract was fractionated and the ECIS method permitted the distinction of specific kinetic patterns of cytotoxicity on the fractions as well as the extract's pure constituents. This study offers evidence that ECIS is an excellent tool for real-time monitoring of the cytotoxicity of complex extracts that are difficult to work with using conventional (label-based) assays. Altogether, it offers a very suitable cytotoxicity-screening assay making the work with natural products less challenging within the drug discovery workflow.

  18. Characterization and optimization of 1-Aminocyclopropane-1-Carboxylate Deaminase (ACCD activity in different rhizospheric PGPR along with Microbacterium sp. strain ECI-12A

    Directory of Open Access Journals (Sweden)

    Ashok Kumar

    2013-03-01

    Full Text Available A total of nine strains of plant growth promoting rhizobacteria were analyzed for ACC deaminase activity, where highest ACC deaminase activity was found in Klebsiella sp strain ECI-10A (539.1 nmol α-keto butyrate/ mg protein/ h and lowest in Microbacterium sp strain ECI-12A (122.0 nmol α-keto butyrate/ mg protein/ h. Although Microbacterium sp strain ECI-12A showed lowest level of ACC deaminase activity, but, the species of Microbacterium isolated from rhizosphere is the first report. Microbacterium sp strain ECI-12A was also analyzed under varying conditions of time, amount of 1-Aminocyclopropane-1- carboxylate (ACC, and temperature for optimization of the ACC deaminase activity. The optimum activity was recorded with the supplementation of 5mM ACC at 30oC temperature after 24h of culture growth. All the nine strains showed acdS gene in the PCR amplification of that gene. No any rhizospheric Microbacterium species showing ACC deaminase activity have been reported earlier, therefore, we report here ACC deaminase activity in Microbacterium sp ECI-12A isolated from rice rhizosphere is a novel finding.

  19. Efficient programming of human eye conjunctiva-derived induced pluripotent stem (ECiPS) cells into definitive endoderm-like cells.

    Science.gov (United States)

    Massumi, Mohammad; Hoveizi, Elham; Baktash, Parvaneh; Hooti, Abdollah; Ghazizadeh, Leili; Nadri, Samad; Pourasgari, Farzaneh; Hajarizadeh, Athena; Soleimani, Masoud; Nabiuni, Mohammad; Khorramizadeh, Mohammad R

    2014-03-10

    Due to pluripotency of induced pluripotent stem (iPS) cells, and the lack of immunological incompatibility and ethical issues, iPS cells have been considered as an invaluable cell source for future cell replacement therapy. This study was aimed first at establishment of novel iPS cells, ECiPS, which directly reprogrammed from human Eye Conjunctiva-derived Mesenchymal Stem Cells (EC-MSCs); second, comparing the inductive effects of Wnt3a/Activin A biomolecules to IDE1 small molecule in derivation of definitive endoderm (DE) from the ECiPS cells. To that end, first, the EC-MSCs were transduced by SOKM-expressing lentiviruses and characterized for endogenous expression of embryonic markers Then the established ECiPS cells were induced to DE formation by Wnt3a/Activin A or IDE1. Quantification of GSC, Sox17 and Foxa2 expression, as DE-specific markers, in both mRNA and protein levels revealed that induction of ECiPS cells by either Wnt3a/Activin A or IDE1 could enhance the expression level of the genes; however the levels of increase were higher in Wnt3a/Activin A induced ECiPS-EBs than IDE1 induced cells. Furthermore, the flow cytometry analyses showed no synergistic effect between Activin A and Wnt3a to derive DE-like cells from ECiPS cells. The comparative findings suggest that although both Wnt3a/Activin A signaling and IDE1 molecule could be used for differentiation of iPS into DE cells, the DE-inducing effect of Wnt3a/Activin A was statistically higher than IDE1.

  20. 78 FR 63570 - Proposed Collection; Comment Request for Forms W-8BEN, W-8BEN-E, W-8ECI, W-8EXP, and W-8IMY

    Science.gov (United States)

    2013-10-24

    ... Internal Revenue Service Proposed Collection; Comment Request for Forms W-8BEN, W-8BEN-E, W-8ECI, W-8EXP, and W-8IMY AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and request for comments... Form W-8BEN, Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding,...

  1. ECI-4 screening of attention deficit-hyperactivity disorder and co-morbidity in Mexican preschool children: preliminary results Tamizaje del trastorno por déficit de atención-hiperactividad y su co-morbilidad en preescolares mexicanos por el ECI-4: resultados preliminares

    Directory of Open Access Journals (Sweden)

    Adrián Poblano

    2006-12-01

    Full Text Available OBJECTIVE: To examine prospectively usefulness of Early Childhood Inventory-4 (ECI-4 in identifying attention deficit-hyperactivity disorder (ADHD, oppositional defiant disorder (ODD, and conduct disorder (CD. METHOD: A sample of children OBJETIVO: Examinar prospectivamente la utilidad del Inventario Temprano de la Niñez-4 (Early Childhood Inventory-4, ECI-4 para identificar el trastorno por déficit de atención-hiperactividad (TDAH, el trastorno desafiante-oposicional (TDO y el trastorno de conducta (TC. MÉTODO: Una muestra de niños <6 años fue evaluada con el ECI-4 en un ambiente escolar y los resultados comparados con los de las Escalas de Conners (Conners Rating Scales-Revised, CRS-R 6 meses mas tarde. La muestra consistió de 34 niños (20 niños, 14 niñas seguidos prospectivamente. RESULTADOS: La frecuencia de niños que llenaron los criterios del DSM-IV para TDAH en la escala para padres del ECI-4 fue 17%, mientras que en la escala para maestros fue 32%. La frecuencia de niños que llenaron los criterios del DSM-IV para TDA-H en la escala para padres CRS-R fue 20%, en la escala para maestros fue 23%. Se hallaron correlaciones significativas entre la escala para maestros del ECI-4 y las escalas para maestros y para padres de CRS-R. La sensibilidad y la especificidad de las escalas para maestros y padres del ECI-4 no fueron alentadoras. La frecuencia del TDO identificada en la escala para padres del ECI-4 fue 5% y en la escala para maestros fue 17%. La frecuencia del TDO en la escala para padres y para maestros CRS-R fue 17%. El TC no fue identificado por los padres con la escala del ECI-4, pero en la escala para maestros, la frecuencia fue de 14%. CONCLUSIÓN: Los resultados obtenidos apoyan parcialmente el uso de las escalas de tamizaje del ECI-4 para encontrar TDAH, TDO y TC en preescolares mexicanos.

  2. DOE Advanced Scientific Computing Advisory Committee (ASCAC) Report: Exascale Computing Initiative Review

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Daniel [University of Iowa; Berzins, Martin [University of Utah; Pennington, Robert; Sarkar, Vivek [Rice University; Taylor, Valerie [Texas A& M University

    2015-08-01

    On November 19, 2014, the Advanced Scientific Computing Advisory Committee (ASCAC) was charged with reviewing the Department of Energy’s conceptual design for the Exascale Computing Initiative (ECI). In particular, this included assessing whether there are significant gaps in the ECI plan or areas that need to be given priority or extra management attention. Given the breadth and depth of previous reviews of the technical challenges inherent in exascale system design and deployment, the subcommittee focused its assessment on organizational and management issues, considering technical issues only as they informed organizational or management priorities and structures. This report presents the observations and recommendations of the subcommittee.

  3. Characterization of 2 MeV, 4 MeV, 6 MeV and 18 MeV buildup caps for use with a 0.6 cubic centimeter thimble ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Salyer, R.L.; VanDenburg, J.W.; Prinja, A.K.; Kirby, T.; Busch, R. [Univ. of New Mexico, Albuquerque, NM (United States); Hong-Nian Jow [Sandia National Laboratories, Albuquerque, NM (United States)

    1996-07-01

    The purpose of this research is to characterize existing 2 MeV, 4 MeV and 6 MeV buildup caps, and to determine if a buildup cap can be made for the 0.6 cm{sup 3} thimble ionization chamber that will accurately measure exposures in a high-energy photon radiation field. Two different radiation transport codes were used to computationally characterize existing 2 MeV, 4 MeV, and 6 MeV buildup caps for a 0.6 cm{sup 3} active volume thimble ionization chamber: ITS, The Integrated TIGER Series of Coupled Electron-Photon Monte Carlo Transport Codes; and CEPXS/ONEDANT, A One-Dimensional Coupled Electron-Photon Discrete Ordinates Code Package. These codes were also used to determine the design characteristics of a buildup cap for use in the 18 MeV photon beam produced by the 14 TW pulsed power HERMES-III electron accelerator. The maximum range of the secondary electron, the depth at which maximum dose occurs, and the point where dose and collision kerma are equal have been determined to establish the validity of electronic equilibrium. The ionization chamber with the appropriate buildup cap was then subjected to a 4 MeV and a 6 MeV bremmstrahlung radiation spectrum to determine the detector response.

  4. Presenting the ECO: Evolutionary Computation Ontology

    NARCIS (Netherlands)

    Yaman, Anil; Hallawa, Ahmed; Coler, Matthew; Iacca, Giovanni

    2017-01-01

    A well-established notion in Evolutionary Computation (EC)is the importance of the balance between exploration and exploitation.Data structures (e.g. for solution encoding), evolutionary operators, se-lection and fitness evaluation facilitate this balance. Furthermore, theability of an Evolutionary

  5. Comparison of Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for measurement of cardiac troponin I.

    Science.gov (United States)

    Kao, J T; Wong, I L; Lee, J Y; Chen, R C

    2001-03-01

    Myocardial infarction is a common cause of morbidity and mortality in patients with chest pain. The presence of human cardiac troponin I (cTnI) in serum is considered to be a highly specific biochemical marker of acute myocardial infarction. In this study we compare the performances of the Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for the measurement of cTnI. The first two methods use a fluorogenic enzyme-linked immunoassay. whereas the last two use chemiluminescent immunometric assays. All procedures are completely automated. Total percentage coefficients of variation using pooled sera ranged from 5.9 to 6.5% for the AxSYM, 14.4 to 25.6% for the Opus, 6.9 to 9.8% for the Immulite and 4.5 to 5.2% for the Vitros ECi method. The closest correlation between methods, obtained from 120 fresh serum samples, was observed between the Vitros ECi and the Immulite methods, with r=0.99, and the regression line was Immulite cTnI 1.505 (95% confidence interval 1.474-1.536) x Vitros cTnI--0.154 (-0.702 to 0.394). Receiver operating characteristic curves were nearly identical for all assays, and the areas under the curves were 0.972, 0.927, 0.967 and 0.969 for the AxSYM, Opus, Immulite and Vitros ECi methods, respectively. There was a significant difference between the AxSYM and Opus methods (P= 0.036).

  6. Computational investigation of 99Mo, 89Sr, and 131I production rates in a subcritical UO2(NO32 aqueous solution reactor driven by a 30-MeV proton accelerator

    Directory of Open Access Journals (Sweden)

    Z. Gholamzadeh

    2015-12-01

    Full Text Available The use of subcritical aqueous homogenous reactors driven by accelerators presents an attractive alternative for producing 99Mo. In this method, the medical isotope production system itself is used to extract 99Mo or other radioisotopes so that there is no need to irradiate common targets. In addition, it can operate at much lower power compared to a traditional reactor to produce the same amount of 99Mo by irradiating targets. In this study, the neutronic performance and 99Mo, 89Sr, and 131I production capacity of a subcritical aqueous homogenous reactor fueled with low-enriched uranyl nitrate was evaluated using the MCNPX code. A proton accelerator with a maximum 30-MeV accelerating power was used to run the subcritical core. The computational results indicate a good potential for the modeled system to produce the radioisotopes under completely safe conditions because of the high negative reactivity coefficients of the modeled core. The results show that application of an optimized beam window material can increase the fission power of the aqueous nitrate fuel up to 80%. This accelerator-based procedure using low enriched uranium nitrate fuel to produce radioisotopes presents a potentially competitive alternative in comparison with the reactor-based or other accelerator-based methods. This system produces ∼1,500 Ci/wk (∼325 6-day Ci of 99Mo at the end of a cycle.

  7. Performance of the 6 MeV injector for the Moscow racetrack microtron

    Science.gov (United States)

    Alimov, A. S.; Chepurnov, A. S.; Chubarov, O. V.; Gribov, I. V.; Ishkhanov, B. S.; Piskarev, I. M.; Rzhanov, A. G.; Sotnikov, M. A.; Surma, I. V.; Shumakov, A. V.; Shvedunov, V. I.; Tiunov, A. V.; Ushkanov, V. A.

    1993-03-01

    The 6 MeV injector for the Moscow racetrack microtron is described. The work presents the accelerator description, the rf power supply system and results of the computer simulation. The method of injector tuning and experimental results are discussed.

  8. Synthesis and SHG properties of two new cyanurates: Sr3(O3C3N3)2 (SCY) and Eu3(O3C3N3)2 (ECY).

    Science.gov (United States)

    Kalmutzki, Markus; Ströbele, Markus; Wackenhut, Frank; Meixner, Alfred J; Meyer, H-Jürgen

    2014-12-01

    The new cyanurates Sr3(O3C3N3)2 (SCY) and Eu3(O3C3N3)2 (ECY) were prepared via exothermic solid state metathesis reactions from MCl2 (M = Sr, Eu) and K(OCN) in silica tubes at 525 °C. Both structures were characterized by means of powder and single crystal X-ray diffraction, and their structures are shown to crystallize with the noncentrosymmetric space group R3c (No. 161). Infrared spectra and nonlinear optical properties (NLO) of SCY and ECY are reported in comparison to those of CCY and β-BaB2O4 (β-BBO).

  9. Textural analyses of carbon fiber materials by 2D-FFT of complex images obtained by high frequency eddy current imaging (HF-ECI)

    Science.gov (United States)

    Schulze, Martin H.; Heuer, Henning

    2012-04-01

    Carbon fiber based materials are used in many lightweight applications in aeronautical, automotive, machine and civil engineering application. By the increasing automation in the production process of CFRP laminates a manual optical inspection of each resin transfer molding (RTM) layer is not practicable. Due to the limitation to surface inspection, the quality parameters of multilayer 3 dimensional materials cannot be observed by optical systems. The Imaging Eddy- Current (EC) NDT is the only suitable inspection method for non-resin materials in the textile state that allows an inspection of surface and hidden layers in parallel. The HF-ECI method has the capability to measure layer displacements (misaligned angle orientations) and gap sizes in a multilayer carbon fiber structure. EC technique uses the variation of the electrical conductivity of carbon based materials to obtain material properties. Beside the determination of textural parameters like layer orientation and gap sizes between rovings, the detection of foreign polymer particles, fuzzy balls or visualization of undulations can be done by the method. For all of these typical parameters an imaging classification process chain based on a high resolving directional ECimaging device named EddyCus® MPECS and a 2D-FFT with adapted preprocessing algorithms are developed.

  10. <600> MeV synchro-cyclotron

    CERN Multimedia

    1971-01-01

    One of the 14 pancakes of the new magnet coils for the 600 MeV synchro-cyclotron which were wound and coated with epoxy resin on the CERN site. These new coils will replace the present ones which have been in use for more than 14 years but are now showing signs of deteriorations.

  11. MeV fullerene impacts on mica

    Energy Technology Data Exchange (ETDEWEB)

    Doebeli, M.; Scandella, L. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ames, F. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Hillock heights on mica irradiated with MeV C{sub 60} ions have been investigated systematically. Results show that the small range of secondary particles along the track plays a crucial role in defect production. (author) figs., tab., refs.

  12. A proposed diagnostic for time-resolved 14 MeV neutron measurements on TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Ku, L.P.; Nazikian, R.; Prorvitch, V.

    1990-06-01

    A novel method for time resolved measurements of the 14 MeV neutron flux in an intense 2.5 MeV neutron and {gamma}-ray background has been developed. Discrimination against the background 2.5 MeV neutron and {gamma}-ray flux is achieved by the use of polyethylene and lead shielding. A high detection efficiency of DT neutrons is obtained by the use of large volume plastic scintillators and photomultiplier tube designed for operating in high magnetic field environments. Design computations for a such a detector system on TFTR show that an absolute detection efficiency of {approximately}10{sup {minus}8} counts per DT neutron may be obtained. A source strength of 10{sup 13} DT n/s may readily be detected by this method using both count mode and current mode operation with a resolution of {approximately}10 ms within a statistical accuracy of {approximately}5%. 12 refs., 8 figs., 2 tabs.

  13. Photonuclear reaction based high-energy x-ray spectrometer to cover from 2 MeV to 20 MeV.

    Science.gov (United States)

    Sakata, S; Arikawa, Y; Kojima, S; Ikenouchi, T; Nagai, T; Abe, Y; Inoue, H; Morace, A; Utsugi, M; Kato, R; Nishimura, H; Nakai, M; Shiraga, H; Fujioka, S; Azechi, H

    2014-11-01

    A photonuclear-reaction-based hard x-ray spectrometer is developed to measure the number and energy spectrum of fast electrons generated by interactions between plasma and intense laser light. In this spectrometer, x-rays are converted to neutrons through photonuclear reactions, and the neutrons are counted with a bubble detector that is insensitive to x-rays. The spectrometer consists of a bundle of hard x-ray detectors that respond to different photon-energy ranges. Proof-of-principle experiment was performed on a linear accelerator facility. A quasi-monoenergetic electron bunch (Ne = 1.0 × 10(-6) C, Ee = 16 ± 0.32 MeV) was injected into a 5-mm-thick lead plate. Bremsstrahlung x-rays, which emanate from the lead plate, were measured with the spectrometer. The measured spectral shape and intensity agree fairly well with those computed with a Monte Carlo simulation code. The result shows that high-energy x-rays can be measured absolutely with a photon-counting accuracy of 50%-70% in the energy range from 2 MeV to 20 MeV with a spectral resolution (Δhν/hν) of about 15%. Quantum efficiency of this spectrometer was designed to be 10(-7), 10(-4), 10(-5), respectively, for 2-10, 11-15, and 15-25 MeV of photon energy ranges.

  14. COMPUTING

    CERN Multimedia

    M. Kasemann

    Overview In autumn the main focus was to process and handle CRAFT data and to perform the Summer08 MC production. The operational aspects were well covered by regular Computing Shifts, experts on duty and Computing Run Coordination. At the Computing Resource Board (CRB) in October a model to account for service work at Tier 2s was approved. The computing resources for 2009 were reviewed for presentation at the C-RRB. The quarterly resource monitoring is continuing. Facilities/Infrastructure operations Operations during CRAFT data taking ran fine. This proved to be a very valuable experience for T0 workflows and operations. The transfers of custodial data to most T1s went smoothly. A first round of reprocessing started at the Tier-1 centers end of November; it will take about two weeks. The Computing Shifts procedure was tested full scale during this period and proved to be very efficient: 30 Computing Shifts Persons (CSP) and 10 Computing Resources Coordinators (CRC). The shift program for the shut down w...

  15. COMPUTING

    CERN Multimedia

    M. Kasemann

    Overview During the past three months activities were focused on data operations, testing and re-enforcing shift and operational procedures for data production and transfer, MC production and on user support. Planning of the computing resources in view of the new LHC calendar in ongoing. Two new task forces were created for supporting the integration work: Site Commissioning, which develops tools helping distributed sites to monitor job and data workflows, and Analysis Support, collecting the user experience and feedback during analysis activities and developing tools to increase efficiency. The development plan for DMWM for 2009/2011 was developed at the beginning of the year, based on the requirements from the Physics, Computing and Offline groups (see Offline section). The Computing management meeting at FermiLab on February 19th and 20th was an excellent opportunity discussing the impact and for addressing issues and solutions to the main challenges facing CMS computing. The lack of manpower is particul...

  16. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction CMS distributed computing system performed well during the 2011 start-up. The events in 2011 have more pile-up and are more complex than last year; this results in longer reconstruction times and harder events to simulate. Significant increases in computing capacity were delivered in April for all computing tiers, and the utilisation and load is close to the planning predictions. All computing centre tiers performed their expected functionalities. Heavy-Ion Programme The CMS Heavy-Ion Programme had a very strong showing at the Quark Matter conference. A large number of analyses were shown. The dedicated heavy-ion reconstruction facility at the Vanderbilt Tier-2 is still involved in some commissioning activities, but is available for processing and analysis. Facilities and Infrastructure Operations Facility and Infrastructure operations have been active with operations and several important deployment tasks. Facilities participated in the testing and deployment of WMAgent and WorkQueue+Request...

  17. COMPUTING

    CERN Multimedia

    P. McBride

    The Computing Project is preparing for a busy year where the primary emphasis of the project moves towards steady operations. Following the very successful completion of Computing Software and Analysis challenge, CSA06, last fall, we have reorganized and established four groups in computing area: Commissioning, User Support, Facility/Infrastructure Operations and Data Operations. These groups work closely together with groups from the Offline Project in planning for data processing and operations. Monte Carlo production has continued since CSA06, with about 30M events produced each month to be used for HLT studies and physics validation. Monte Carlo production will continue throughout the year in the preparation of large samples for physics and detector studies ramping to 50 M events/month for CSA07. Commissioning of the full CMS computing system is a major goal for 2007. Site monitoring is an important commissioning component and work is ongoing to devise CMS specific tests to be included in Service Availa...

  18. COMPUTING

    CERN Multimedia

    I. Fisk

    2013-01-01

    Computing activity had ramped down after the completion of the reprocessing of the 2012 data and parked data, but is increasing with new simulation samples for analysis and upgrade studies. Much of the Computing effort is currently involved in activities to improve the computing system in preparation for 2015. Operations Office Since the beginning of 2013, the Computing Operations team successfully re-processed the 2012 data in record time, not only by using opportunistic resources like the San Diego Supercomputer Center which was accessible, to re-process the primary datasets HTMHT and MultiJet in Run2012D much earlier than planned. The Heavy-Ion data-taking period was successfully concluded in February collecting almost 500 T. Figure 3: Number of events per month (data) In LS1, our emphasis is to increase efficiency and flexibility of the infrastructure and operation. Computing Operations is working on separating disk and tape at the Tier-1 sites and the full implementation of the xrootd federation ...

  19. Computer

    CERN Document Server

    Atkinson, Paul

    2011-01-01

    The pixelated rectangle we spend most of our day staring at in silence is not the television as many long feared, but the computer-the ubiquitous portal of work and personal lives. At this point, the computer is almost so common we don't notice it in our view. It's difficult to envision that not that long ago it was a gigantic, room-sized structure only to be accessed by a few inspiring as much awe and respect as fear and mystery. Now that the machine has decreased in size and increased in popular use, the computer has become a prosaic appliance, little-more noted than a toaster. These dramati

  20. COMPUTING

    CERN Multimedia

    I. Fisk

    2010-01-01

    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion An activity that is still in progress is computing for the heavy-ion program. The heavy-ion events are collected without zero suppression, so the event size is much large at roughly 11 MB per event of RAW. The central collisions are more complex and...

  1. COMPUTING

    CERN Multimedia

    M. Kasemann P. McBride Edited by M-C. Sawley with contributions from: P. Kreuzer D. Bonacorsi S. Belforte F. Wuerthwein L. Bauerdick K. Lassila-Perini M-C. Sawley

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the comput...

  2. COMPUTING

    CERN Multimedia

    I. Fisk

    2010-01-01

    Introduction The first data taking period of November produced a first scientific paper, and this is a very satisfactory step for Computing. It also gave the invaluable opportunity to learn and debrief from this first, intense period, and make the necessary adaptations. The alarm procedures between different groups (DAQ, Physics, T0 processing, Alignment/calibration, T1 and T2 communications) have been reinforced. A major effort has also been invested into remodeling and optimizing operator tasks in all activities in Computing, in parallel with the recruitment of new Cat A operators. The teams are being completed and by mid year the new tasks will have been assigned. CRB (Computing Resource Board) The Board met twice since last CMS week. In December it reviewed the experience of the November data-taking period and could measure the positive improvements made for the site readiness. It also reviewed the policy under which Tier-2 are associated with Physics Groups. Such associations are decided twice per ye...

  3. COMPUTING

    CERN Multimedia

    P. McBride

    It has been a very active year for the computing project with strong contributions from members of the global community. The project has focused on site preparation and Monte Carlo production. The operations group has begun processing data from P5 as part of the global data commissioning. Improvements in transfer rates and site availability have been seen as computing sites across the globe prepare for large scale production and analysis as part of CSA07. Preparations for the upcoming Computing Software and Analysis Challenge CSA07 are progressing. Ian Fisk and Neil Geddes have been appointed as coordinators for the challenge. CSA07 will include production tests of the Tier-0 production system, reprocessing at the Tier-1 sites and Monte Carlo production at the Tier-2 sites. At the same time there will be a large analysis exercise at the Tier-2 centres. Pre-production simulation of the Monte Carlo events for the challenge is beginning. Scale tests of the Tier-0 will begin in mid-July and the challenge it...

  4. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction During the past six months, Computing participated in the STEP09 exercise, had a major involvement in the October exercise and has been working with CMS sites on improving open issues relevant for data taking. At the same time operations for MC production, real data reconstruction and re-reconstructions and data transfers at large scales were performed. STEP09 was successfully conducted in June as a joint exercise with ATLAS and the other experiments. It gave good indication about the readiness of the WLCG infrastructure with the two major LHC experiments stressing the reading, writing and processing of physics data. The October Exercise, in contrast, was conducted as an all-CMS exercise, where Physics, Computing and Offline worked on a common plan to exercise all steps to efficiently access and analyze data. As one of the major results, the CMS Tier-2s demonstrated to be fully capable for performing data analysis. In recent weeks, efforts were devoted to CMS Computing readiness. All th...

  5. COMPUTING

    CERN Multimedia

    M. Kasemann

    CCRC’08 challenges and CSA08 During the February campaign of the Common Computing readiness challenges (CCRC’08), the CMS computing team had achieved very good results. The link between the detector site and the Tier0 was tested by gradually increasing the number of parallel transfer streams well beyond the target. Tests covered the global robustness at the Tier0, processing a massive number of very large files and with a high writing speed to tapes.  Other tests covered the links between the different Tiers of the distributed infrastructure and the pre-staging and reprocessing capacity of the Tier1’s: response time, data transfer rate and success rate for Tape to Buffer staging of files kept exclusively on Tape were measured. In all cases, coordination with the sites was efficient and no serious problem was found. These successful preparations prepared the ground for the second phase of the CCRC’08 campaign, in May. The Computing Software and Analysis challen...

  6. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction It has been a very active quarter in Computing with interesting progress in all areas. The activity level at the computing facilities, driven by both organised processing from data operations and user analysis, has been steadily increasing. The large-scale production of simulated events that has been progressing throughout the fall is wrapping-up and reprocessing with pile-up will continue. A large reprocessing of all the proton-proton data has just been released and another will follow shortly. The number of analysis jobs by users each day, that was already hitting the computing model expectations at the time of ICHEP, is now 33% higher. We are expecting a busy holiday break to ensure samples are ready in time for the winter conferences. Heavy Ion The Tier 0 infrastructure was able to repack and promptly reconstruct heavy-ion collision data. Two copies were made of the data at CERN using a large CASTOR disk pool, and the core physics sample was replicated ...

  7. COMPUTING

    CERN Multimedia

    I. Fisk

    2012-01-01

    Introduction Computing continued with a high level of activity over the winter in preparation for conferences and the start of the 2012 run. 2012 brings new challenges with a new energy, more complex events, and the need to make the best use of the available time before the Long Shutdown. We expect to be resource constrained on all tiers of the computing system in 2012 and are working to ensure the high-priority goals of CMS are not impacted. Heavy ions After a successful 2011 heavy-ion run, the programme is moving to analysis. During the run, the CAF resources were well used for prompt analysis. Since then in 2012 on average 200 job slots have been used continuously at Vanderbilt for analysis workflows. Operations Office As of 2012, the Computing Project emphasis has moved from commissioning to operation of the various systems. This is reflected in the new organisation structure where the Facilities and Data Operations tasks have been merged into a common Operations Office, which now covers everything ...

  8. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction More than seventy CMS collaborators attended the Computing and Offline Workshop in San Diego, California, April 20-24th to discuss the state of readiness of software and computing for collisions. Focus and priority were given to preparations for data taking and providing room for ample dialog between groups involved in Commissioning, Data Operations, Analysis and MC Production. Throughout the workshop, aspects of software, operating procedures and issues addressing all parts of the computing model were discussed. Plans for the CMS participation in STEP’09, the combined scale testing for all four experiments due in June 2009, were refined. The article in CMS Times by Frank Wuerthwein gave a good recap of the highly collaborative atmosphere of the workshop. Many thanks to UCSD and to the organizers for taking care of this workshop, which resulted in a long list of action items and was definitely a success. A considerable amount of effort and care is invested in the estimate of the co...

  9. 14 MeV neutrons physics and applications

    CERN Document Server

    Valkovic, Vladivoj

    2015-01-01

    Despite the often difficult and time-consuming effort of performing experiments with fast (14 MeV) neutrons, these neutrons can offer special insight into nucleus and other materials because of the absence of charge. 14 MeV Neutrons: Physics and Applications explores fast neutrons in basic science and applications to problems in medicine, the environment, and security.Drawing on his more than 50 years of experience working with 14 MeV neutrons, the author focuses on:Sources of 14 MeV neutrons, including laboratory size accelerators, small and sealed tube generators, well logging sealed tube ac

  10. Design and Installation of a 10 MeV Small Medical Cyclotron Electrical System

    Institute of Scientific and Technical Information of China (English)

    CAI; Hong-ru; GE; Tao; WU; Long-cheng; LI; Zheng-guo; LIU; Geng-shou

    2012-01-01

    <正>The electrical and pneumatic system of the 10 MeV small medical cyclotron is to provide safe and reliable power supply and relay protection to ensure the stable operation of equipments as well as personnel safety. Based on the equipment installation and operation status of the machine, the computational load of electrical system is designed to be 130 kW. The load grade is three-level, which adopts three-phase

  11. Design of 200 MeV energy spectrum analytic system of linac in NSRL

    CERN Document Server

    Lu Ping; Li We Imin; Xu Hong Liang; Liu Zu Ping; Pei Yuan Ji; Hong Jun; Wang Jun Hua; He Duo Hui

    2002-01-01

    Energy spectrum analytic system of 200 MeV linear accelerator in NSRL is used to detect the beam energy and to guild the machine adjustment. The author shows the former status of the system, and analyses some of its shortcomings. In the NSRL project-II, the system is redesigned, and has been installed recently. The author also describes the results of physics computation and some newest preliminary experiments

  12. COMPUTING

    CERN Multimedia

    Matthias Kasemann

    Overview The main focus during the summer was to handle data coming from the detector and to perform Monte Carlo production. The lessons learned during the CCRC and CSA08 challenges in May were addressed by dedicated PADA campaigns lead by the Integration team. Big improvements were achieved in the stability and reliability of the CMS Tier1 and Tier2 centres by regular and systematic follow-up of faults and errors with the help of the Savannah bug tracking system. In preparation for data taking the roles of a Computing Run Coordinator and regular computing shifts monitoring the services and infrastructure as well as interfacing to the data operations tasks are being defined. The shift plan until the end of 2008 is being put together. User support worked on documentation and organized several training sessions. The ECoM task force delivered the report on “Use Cases for Start-up of pp Data-Taking” with recommendations and a set of tests to be performed for trigger rates much higher than the ...

  13. COMPUTING

    CERN Multimedia

    M. Kasemann

    Introduction A large fraction of the effort was focused during the last period into the preparation and monitoring of the February tests of Common VO Computing Readiness Challenge 08. CCRC08 is being run by the WLCG collaboration in two phases, between the centres and all experiments. The February test is dedicated to functionality tests, while the May challenge will consist of running at all centres and with full workflows. For this first period, a number of functionality checks of the computing power, data repositories and archives as well as network links are planned. This will help assess the reliability of the systems under a variety of loads, and identifying possible bottlenecks. Many tests are scheduled together with other VOs, allowing the full scale stress test. The data rates (writing, accessing and transfer¬ring) are being checked under a variety of loads and operating conditions, as well as the reliability and transfer rates of the links between Tier-0 and Tier-1s. In addition, the capa...

  14. COMPUTING

    CERN Multimedia

    P. MacBride

    The Computing Software and Analysis Challenge CSA07 has been the main focus of the Computing Project for the past few months. Activities began over the summer with the preparation of the Monte Carlo data sets for the challenge and tests of the new production system at the Tier-0 at CERN. The pre-challenge Monte Carlo production was done in several steps: physics generation, detector simulation, digitization, conversion to RAW format and the samples were run through the High Level Trigger (HLT). The data was then merged into three "Soups": Chowder (ALPGEN), Stew (Filtered Pythia) and Gumbo (Pythia). The challenge officially started when the first Chowder events were reconstructed on the Tier-0 on October 3rd. The data operations teams were very busy during the the challenge period. The MC production teams continued with signal production and processing while the Tier-0 and Tier-1 teams worked on splitting the Soups into Primary Data Sets (PDS), reconstruction and skimming. The storage sys...

  15. COMPUTING

    CERN Multimedia

    Contributions from I. Fisk

    2012-01-01

    Introduction The start of the 2012 run has been busy for Computing. We have reconstructed, archived, and served a larger sample of new data than in 2011, and we are in the process of producing an even larger new sample of simulations at 8 TeV. The running conditions and system performance are largely what was anticipated in the plan, thanks to the hard work and preparation of many people. Heavy ions Heavy Ions has been actively analysing data and preparing for conferences.  Operations Office Figure 6: Transfers from all sites in the last 90 days For ICHEP and the Upgrade efforts, we needed to produce and process record amounts of MC samples while supporting the very successful data-taking. This was a large burden, especially on the team members. Nevertheless the last three months were very successful and the total output was phenomenal, thanks to our dedicated site admins who keep the sites operational and the computing project members who spend countless hours nursing the...

  16. COMPUTING

    CERN Multimedia

    I. Fisk

    2012-01-01

      Introduction Computing activity has been running at a sustained, high rate as we collect data at high luminosity, process simulation, and begin to process the parked data. The system is functional, though a number of improvements are planned during LS1. Many of the changes will impact users, we hope only in positive ways. We are trying to improve the distributed analysis tools as well as the ability to access more data samples more transparently.  Operations Office Figure 2: Number of events per month, for 2012 Since the June CMS Week, Computing Operations teams successfully completed data re-reconstruction passes and finished the CMSSW_53X MC campaign with over three billion events available in AOD format. Recorded data was successfully processed in parallel, exceeding 1.2 billion raw physics events per month for the first time in October 2012 due to the increase in data-parking rate. In parallel, large efforts were dedicated to WMAgent development and integrati...

  17. COMPUTING

    CERN Document Server

    2010-01-01

    Introduction Just two months after the “LHC First Physics” event of 30th March, the analysis of the O(200) million 7 TeV collision events in CMS accumulated during the first 60 days is well under way. The consistency of the CMS computing model has been confirmed during these first weeks of data taking. This model is based on a hierarchy of use-cases deployed between the different tiers and, in particular, the distribution of RECO data to T1s, who then serve data on request to T2s, along a topology known as “fat tree”. Indeed, during this period this model was further extended by almost full “mesh” commissioning, meaning that RECO data were shipped to T2s whenever possible, enabling additional physics analyses compared with the “fat tree” model. Computing activities at the CMS Analysis Facility (CAF) have been marked by a good time response for a load almost evenly shared between ALCA (Alignment and Calibration tasks - highest p...

  18. COMPUTING

    CERN Multimedia

    I. Fisk

    2013-01-01

    Computing operation has been lower as the Run 1 samples are completing and smaller samples for upgrades and preparations are ramping up. Much of the computing activity is focusing on preparations for Run 2 and improvements in data access and flexibility of using resources. Operations Office Data processing was slow in the second half of 2013 with only the legacy re-reconstruction pass of 2011 data being processed at the sites.   Figure 1: MC production and processing was more in demand with a peak of over 750 Million GEN-SIM events in a single month.   Figure 2: The transfer system worked reliably and efficiently and transferred on average close to 520 TB per week with peaks at close to 1.2 PB.   Figure 3: The volume of data moved between CMS sites in the last six months   The tape utilisation was a focus for the operation teams with frequent deletion campaigns from deprecated 7 TeV MC GEN-SIM samples to INVALID datasets, which could be cleaned up...

  19. Valine radiolysis by MeV ions

    Science.gov (United States)

    Da Silveira, Enio

    2016-07-01

    Valine, (CH3)2 CHCH (NH2) COOH, is a protein amino acid that has been identified in extraterrestrial environments and in the Murchison meteorite [1]. The knowledge of half-lives of small organic molecules under ionizing radiation is important for the setup of models describing the spread out of prebiotics across the Solar System or the Galaxy. We have investigated typical effects of MeV cosmic ray ions on prebiotic molecules in laboratory by impinging ions produced by the PUC-Rio Van de Graaff accelerator. Pure valine films, deposited by evaporation on KBr substrates, were irradiated by H ^{+}, He ^{+} and N ^{+} ion beams, from 0.5 to 1.5 MeV and up to a fluence of 10 ^{15} projectiles/cm ^{2}. The sample temperature was varied from 10 K to 300 K. The irradiation was interrupted several times for Mid-FTIR analysis of the sample. The main findings are: 1- The column density of the valine decreases exponentially with fluence. 2- In some cases, a second exponential appears in the beginning of irradiation; this feature has been attributed to sample compaction by the ion beam [2]. 3- Destruction cross sections of valine are in the 10 ^{-15} cm ^{2} range, while compaction cross sections are in the 10 ^{-14} cm ^{2} range. 4- Destruction cross section increases with the stopping power of the beam and also with the sample temperature. 5- Surprisingly, during the radiolysis of valine, just CO _{2} is seen by as a daughter molecule formed in the bulk. 6- After long beam fluence, also a CO peak appears in the infrared spectrum; this species is however interpreted as a fragment of the formed CO2 molecules. 7- Considering the flux ratio between laboratory experiments and actual galactic cosmic rays, half-life of valine is predicted for ISM conditions [3]. This work on pure valine is the first measurement of a series. New experiments are planned for determining cross sections of valine dissolved in H _{2}O or CO _{2}, inspired by the study performed for glycine [4]. [1] P

  20. COMPUTING

    CERN Multimedia

    I. Fisk

    2011-01-01

    Introduction The Computing Team successfully completed the storage, initial processing, and distribution for analysis of proton-proton data in 2011. There are still a variety of activities ongoing to support winter conference activities and preparations for 2012. Heavy ions The heavy-ion run for 2011 started in early November and has already demonstrated good machine performance and success of some of the more advanced workflows planned for 2011. Data collection will continue until early December. Facilities and Infrastructure Operations Operational and deployment support for WMAgent and WorkQueue+Request Manager components, routinely used in production by Data Operations, are provided. The GlideInWMS and components installation are now deployed at CERN, which is added to the GlideInWMS factory placed in the US. There has been new operational collaboration between the CERN team and the UCSD GlideIn factory operators, covering each others time zones by monitoring/debugging pilot jobs sent from the facto...

  1. 150 MeV fixed field alternating gradient (FFAG) accelerator

    CERN Document Server

    Nakano, J

    2002-01-01

    150 MeV FFAG accelerator is prototype for practical use. Fundamental development of FFAG, research of FFAG accelerator and its application for therapy are investigated. 150 MeV ring consists of 12 sector magnets. The distribution of magnetic field of 12 sector magnets is almost same. 12 MeV proton beam is generated by cyclotron and injection to 150 MeV FFAG. The injection system consists of 2 bump magnets, kicker magnet and septum electrode. RF accelerating cavity system using high-permeability magnetic substance with high magnetic permeability accelerates proton beam to 150 MeV, then the first operation aims at 250 Hz. Return Yoke Free magnet was developed for adjustment. 150 MeV FFAG magnet is constructed and 12 MeV proton beam acceleration is conformed. The final state of 150 MeV FFAG magnet is explained by calculation results. On cancer therapy by proton beam, the three dimensions spot scan method is proposed. (S.Y.)

  2. RF Operation for the 100MeV Proton Linac

    Energy Technology Data Exchange (ETDEWEB)

    Seol, Kyung Tae; Kwon, Hyeok Jung; Kim, Dae Il; Kim, Han Sung; Song, Young Gi; Jang, Ji Ho; Cho, Yong Sub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The RF systems for the 100MeV linac were constructed. The HPRF system including klystrons, circulators, high power dummy loads, and waveguide components was installed at the klystron gallery, and the LLRF control systems including a commercial FPGA module and a LLRF analog chassis were also installed. The phase stability of the RF reference line was measured with S11 phase under temperature control. The RF systems for 100MeV linac have been operated for a beam commissioning, and the 100MeV proton beam has been supplied to users currently. The RF systems of the 100MeV proton linac for the KOMAC (KOrea Multi-purpose Accelerator Complex) were installed at the Gyeong-ju site. The 100MeV linac consists of a 3MeV RFQ, a 20MeV DTL with four tanks, two MEBT tanks, and seven 100MeV DTL tanks. For the 100MeV linac, nine sets of LLRF control systems and the HPRF systems including 1MW klystrons, circulators and waveguide components have been installed at the klystron gallery, and four high voltage converter modulators to drive nine klystrons have been installed at the modulator room. A RF reference system distributing 300MHz LO signal to each RF control system has also been installed with a temperature control system at the klystron gallery. The requirement of RF field control is within +/- 1% in RF amplitude and +/- 1 degree in RF phase. The RF systems have been operated for the beam commissioning. The installation and operation of the RF system for the 100MeV proton linac are presented in this paper.

  3. Photonuclear reaction based high-energy x-ray spectrometer to cover from 2 MeV to 20 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Sakata, S., E-mail: sakata-s@ile.osaka-u.ac.jp; Arikawa, Y.; Kojima, S.; Ikenouchi, T.; Nagai, T.; Abe, Y.; Inoue, H.; Morace, A.; Utsugi, M.; Nishimura, H.; Nakai, M.; Shiraga, H.; Fujioka, S.; Azechi, H. [Institute of Laser Engineering, Osaka University, Suita 565-0871 (Japan); Kato, R. [Institute of Scientific and Industrial Research, Osaka University, Ibaraki 565-0047 (Japan)

    2014-11-15

    A photonuclear-reaction-based hard x-ray spectrometer is developed to measure the number and energy spectrum of fast electrons generated by interactions between plasma and intense laser light. In this spectrometer, x-rays are converted to neutrons through photonuclear reactions, and the neutrons are counted with a bubble detector that is insensitive to x-rays. The spectrometer consists of a bundle of hard x-ray detectors that respond to different photon-energy ranges. Proof-of-principle experiment was performed on a linear accelerator facility. A quasi-monoenergetic electron bunch (N{sub e} = 1.0 × 10{sup −6} C, E{sub e} = 16 ± 0.32 MeV) was injected into a 5-mm-thick lead plate. Bremsstrahlung x-rays, which emanate from the lead plate, were measured with the spectrometer. The measured spectral shape and intensity agree fairly well with those computed with a Monte Carlo simulation code. The result shows that high-energy x-rays can be measured absolutely with a photon-counting accuracy of 50%–70% in the energy range from 2 MeV to 20 MeV with a spectral resolution (Δhν/hν) of about 15%. Quantum efficiency of this spectrometer was designed to be 10{sup −7}, 10{sup −4}, 10{sup −5}, respectively, for 2–10, 11–15, and 15–25 MeV of photon energy ranges.

  4. COMPUTING

    CERN Multimedia

    M. Kasemann

    CMS relies on a well functioning, distributed computing infrastructure. The Site Availability Monitoring (SAM) and the Job Robot submission have been very instrumental for site commissioning in order to increase availability of more sites such that they are available to participate in CSA07 and are ready to be used for analysis. The commissioning process has been further developed, including "lessons learned" documentation via the CMS twiki. Recently the visualization, presentation and summarizing of SAM tests for sites has been redesigned, it is now developed by the central ARDA project of WLCG. Work to test the new gLite Workload Management System was performed; a 4 times increase in throughput with respect to LCG Resource Broker is observed. CMS has designed and launched a new-generation traffic load generator called "LoadTest" to commission and to keep exercised all data transfer routes in the CMS PhE-DEx topology. Since mid-February, a transfer volume of about 12 P...

  5. Cross sections from proton irradiation of thorium at 800 MeV

    CERN Document Server

    Engle, Jonathan W; Weidner, John W; Wolfsberg, Laura E; Fassbender, Michael E; Jackman, Kevin; Couture, Aaron; Bitteker, Leo J; Ullmann, John L; Gulley, Mark S; Pillai, Chandra; John, Kevin D; Birnbaum, Eva R; Nortier, Francois M

    2013-01-01

    Nuclear formation cross sections are reported for 65 nuclides produced from 800-MeV proton irradiation of thorium foils. These data are useful as benchmarks for computational predictions in the ongoing process of theoretical code development and also to the design of spallation-based radioisotope production currently being considered for multiple radiotherapeutic pharmaceutical agents. Measured data are compared with the predictions of three MCNP6 event generators and used to evaluate the potential for 800-MeV productions of radioisotopes of interest for medical radiotherapy. In only a few instances code predictions are discrepant from measured values by more than a factor of two, demonstrating satisfactory predictive power across a large mass range. Similarly, agreement between measurements presented here and those previously reported is good, lending credibility to predictions of target yields and radioimpurities for high-energy accelerator-produced radionuclides.

  6. Photonuclear and Radiation Effects Testing with a Refurbished 20 MeV Medical Electron Linac

    CERN Document Server

    Webb, Timothy; Beezhold, Wendland; De Veaux, Linda C; Harmon, Frank; Petrisko, Jill E; Spaulding, Randy

    2005-01-01

    An S-band 20 MeV electron linear accelerator formerly used for medical applications has been recommissioned to provide a wide range of photonuclear activation studies as well as various radiation effects on biological and microelectronic systems. Four radiation effect applications involving the electron/photon beams are described. Photonuclear activation of a stable isotope of oxygen provides an active means of characterizing polymer degradation. Biological irradiations of microorganisms including bacteria were used to study total dose and dose rate effects on survivability and the adaptation of these organisms to repeated exposures. Microelectronic devices including bipolar junction transistors (BJTs) and diodes were irradiated to study photocurrent from these devices as a function of peak dose rate with comparisons to computer modeling results. In addition, the 20 MeV linac may easily be converted to a medium energy neutron source which has been used to study neutron damage effects on transistors.

  7. Dosimetric comparison of 4 MeV and 6 MeV electron beams for total skin irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung In; Park, So Yeon; Park, Jong Min; Ye, Sung Joon; Kim, Il Han [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-11-15

    Total skin electron irradiation (TSEI) was developed by Stanford University in the 1950s and introduced for the treatment of mycosis fungoides, the most common form of cutaneous T-cell lymphoma which generally affects the skin. In this study, dosimetric aspects of TSEI consisting of a 4 MeV beam with no spoiler were investigated in comparison to a nominal 6 MeV beam applications was evaluated. The suggested 4 MeV beam for TSEI could be applied to shallow depth skin diseases and to electron boost as second treatment course.

  8. MeV Pulsars: Modeling Spectra and Polarization

    Science.gov (United States)

    Kust Harding, Alice; Kalapotharakos, Constantinos

    2017-08-01

    A sub-population of energetic rotation-powered pulsars show high fluxes of pulsed non-thermal hard X-ray emission. While this ‘MeV pulsar’ population includes some radio-loud pulsars like the Crab and PSR B1509-58, a significant number have no detected radio or GeV emission, a mystery since gamma-ray emission is a common characteristic of pulsars with high spin-down power. Their steeply rising hard X-ray spectral energy distributions (SEDs) suggest peaks at 0.1 - 1 MeV but they have not been detected above 200 keV. Several upcoming and planned telescopes may shed light on the MeV pulsars. The Neutron star Interior Composition ExploreR (NICER) will observe pulsars in the 0.2 - 12 keV band and may discover additional MeV pulsars. The All-Sky Medium-Energy Gamma-Ray Observatory (AMEGO), in a study phase, can detect emission above 0.2 MeV and polarization in the 0.2 - 10 MeV band. We present a model for the spectrum and polarization of MeV pulsars where the X-ray emission comes from electron-positron pairs radiating in the outer magnetosphere and current sheet. This model predicts that the peak of the SED increases with surface magnetic field strength if the pairs are produced in polar cap cascades. For small inclination angles, viewing at large angles to the rotation axis can miss both the radio pulse and the GeV pulse from particles accelerating near the current sheet. Characterizing the emission and geometry of MeV pulsars can thus provide clues to the source of pairs and acceleration in the magnetosphere.

  9. RESIDUAL GAS IONIZATION BEAM PROFILE MONITOR ON 40MeV H— BEAM TRANSPORT LINE

    Institute of Scientific and Technical Information of China (English)

    徐伟鹏; E.Takasaki

    1995-01-01

    The monitor is composed of a pair of electrodes,a single stage of microchannel plate,a phosphor screen,a CCD camera and a PC computer,To obtain a good uniform collecting field,forming electrodes system is used instead of that with a resistive divider,The readout system is performed by the phosphor screen and the CCD camera because the spatial resolution is not limited by the mechanical structure like the anode strip type and such video display system is very useful for beam studies and operation of the 40MeV linac,Besides,the design and test results are described in detail.

  10. Nuclear excitation functions from 40-200 MeV proton irradiation of terbium

    CERN Document Server

    Engle, Jonathan W; Parker, Lauren A; Jackman, Kevin R; Bitteker, Leo J; Ullmann, John L; Gulley, Mark S; Pillai, Chandra; John, Kevin D; Birnbaum, Eva R; Nortier, Francois M

    2015-01-01

    Nuclear formation cross sections are reported for 26 radionuclides, measured with 40 to 200 MeV proton irradiations of terbium foils. These data are relevant to the production of medically relevant radionuclides (e.g., 152Tb, 155Tb, 155Eu, and 156Eu) and to ongoing efforts to characterize stellar nucleosynthesis routes passing through long-lived intermediaries (e.g., 153Gd). Computational predictions from the ALICE2011, CEM03.03, Bertini, and INCL+ABLA codes are compared with newly measured data to contribute to the ongoing process of code development, and yields are calculated for selected radionuclides using measured data.

  11. Comparison of beam simulations with measurements for a 1.25-MeV, CW RFQ

    Energy Technology Data Exchange (ETDEWEB)

    Smith, H.V. Jr.; Bolme, G.O.; Sherman, J.D.; Stevens, R.R. Jr.; Young, L.M.; Zaugg, T.J.

    1998-12-31

    The Low-Energy Demonstration Accelerator (LEDA) injector is tested using the Chalk River Injector Test Stand (CRITS) radio-frequency quadrupole (RFQ) as a diagnostic instrument. Fifty-keV, dc proton beams are injected into the 1.25-MeV, CW RFQ and transported to a beamstop. Computer-simulation-code predictions of the expected beam performance are compared with the measured beam currents and beam profiles. Good agreement is obtained between the measurements and the simulations at the 75-mA design RFQ output current.

  12. Planar Channelling Criticalities of MeV Protons in Si Crystal: Simulations, Evaluation and Applications

    Institute of Scientific and Technical Information of China (English)

    Mukhtar Ahmed Rana

    2008-01-01

    We reports a phase-space structure of MeV proton beam planar channelled along {110} planes in Si crystal using simulation results with the help of a computer code FLUX. The aim is to understand channelling conditions suitable for disorder measurement in crystals. Phase-space distribution of a planar channelled proton beam evolutes in a systematic fashion when it travels into the crystal. Planar channelled beam oscillates between phase-like and space-like conditions in which a part of the beam becomes under phase and space criticalities.These criticality conditions in planar channelling axe analysed, explained and discussed with the perspective of defect measurement in crystals.

  13. Field Flatness Tuning for PEFP 100 MeV DTL

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han-Sung; Kwon, Hyeok-Jung; Seol, Kyung-Tae; Kim, Dae-Il; Cho, Yong-Sub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-05-15

    A conventional 100 MeV drift tube linac is under development for Proton Engineering Frontier Project. Currently the proton linac up to 20 MeV, which consists of injector, 3 MeV RFQ and 20 MeV DTL is completed. To accelerate the proton beam up to 100 MeV additional 7 DTL tanks are required. The DTL should be tuned after fabrication and alignment of the drift tube inside the tank to meet the requirements from the beam dynamics. Tuning process includes the resonant frequency tuning, field flatness tuning and tilt sensitivity tuning. The tuning goal for the field flatness tuning is less than {+-}2% in field uniformity throughout the DTL tank with less than {+-}% standard deviation. A non-uniform field profile caused by the machining errors and alignment errors can be made uniform through the slug tuner adjustment. This procedure requires the field profile measurements and several iterations between the field profile measurements and adjustment. The methods and the results of the DTL field flatness tuning will be reported in this presentation.

  14. Temporal Structure of MeV Electron Precipitation

    Science.gov (United States)

    Millan, R. M.; Lorentzen, K. R.; Lin, R. P.; Smith, D. M.

    2001-12-01

    On January 12, 2000, the MAXIS (MeV Auroral X-ray Imaging and Spectroscopy) long duration balloon experiment was launched from McMurdo, Antarctica carrying x-ray instrumentation designed to search for MeV electron precipitation similar to the event observed in 1996 over Kiruna, Sweden (L=5.8). MAXIS detected seven x-ray bursts with significant flux extending above 0.8 MeV during the 18 day flight in addition to extended periods of softer X-ray activity. These seven events are characterized by an extremely flat spectrum ( ~E-1.7) indicating that the bulk of precipitating electrons producing the x-rays is at relativistic energies. The bursts were detected between magnetic latitudes 58o-67o (corresponding to L-values between 3.8-6.7) with durations varying from several minutes to several hours. The MeV bursts were found to occur preferentially in the late afternoon/dusk sectors (14:30-00:00 MLT) while softer precipitation was detected at all magnetic local times. Two of the strongest MeV events detected by MAXIS show strong modulation of the x-ray count rate at ULF timescales ( ~150 s) similar to modulations observed during the Kiruna event at 100-200 s. We present results from temporal analysis of the MAXIS germanium spectrometer data and examine ground-based and spacecraft observations for evidence of coincident ULF wave activity.

  15. 400-MeV upgrade for the Fermilab linac

    Energy Technology Data Exchange (ETDEWEB)

    Young, D.E.; Noble, R.J.

    1989-09-01

    Fermilab plans to upgrade the Tevatron to expand the physics research program in both the fixed target and the collider operating modes. The first phase of this program is to increase the energy of the H{sup -} linac from 200 to 400 MeV in order to reduce the incoherent space change tuneshift at injection into the Booster which can limit either the brightness or the total intensity of the beam. The linac upgrade will be achieved by replacing the last four 201 MeV, with seven 805 MHz side-coupled cavity modules operating at an average axial field of about 8 MV/m. This will allow acceleration to 400 MeV in the existing Linac enclosure. 4 refs., 3 figs., 1 tab.

  16. 3 MeV Test Stand commissioning report

    CERN Document Server

    Bellodi, Guilia; Andreassen, O; Comblin, J-F; Dimov, V; Lallement, J-B; Martin, C; Midttun, O; Ovalle, E; Raich, U; Roncarolo, F; Rossi, C; Scrivens, R; Vollaire, J; Yarmohammadi Satri, M; Zocca, Z

    2013-01-01

    Linac4 is a normal-conducting 160 MeV H- linear accelerator, presently under construction, that will replace the present 50 MeV Linac2 as injector of the CERN proton accelerator complex with the goal of increasing the LHC luminosity. The Linac4 front-end, composed of a 45 keV ion source, a Low Energy Beam Transport (LEBT), a 352.2 MHz Radio Frequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) housing a beam chopper, was commissioned at the 3 MeV test stand area during the first half of 2013. This report gives details of the installation and operational systems used, describes the commissioning phases and measurements performed and summarizes the results that were finally achieved and the lessons learnt in the process.

  17. Lifetime of 19Ne*(4.03 MeV)

    CERN Document Server

    Kanungo, R; Andreyev, A N; Ball, G C; Chakravarthy, R S; Chicoine, M; Churchman, R; Davids, B; Forster, J S; Gujrathi, S; Hackman, G; Howell, D; Leslie, J R; Morton, A C; Mythili, S; Pearson, C J; Ressler, J J; Ruiz, C; Savajols, H; Schumaker, M A; Tanihata, I; Walden, P L; Yen, S

    2006-01-01

    The Doppler-shift attenuation method was applied to measure the lifetime of the 4.03 MeV state in 19Ne. Utilizing a 3He-implanted Au foil as a target, the state was populated using the 20Ne(3He,alpha)19Ne reaction in inverse kinematics at a 20Ne beam energy of 34 MeV. De-excitation gamma rays were detected in coincidence with alpha particles. At the 1 sigma level, the lifetime was determined to be 11 +4, -3 fs and at the 95.45% confidence level the lifetime is 11 +8, -7 fs.

  18. Resolution considerations in MeV ion microscopy and lithography

    Energy Technology Data Exchange (ETDEWEB)

    Norarat, Rattanaporn, E-mail: rattanaporn@rmutl.ac.th [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Faculty of Sciences and Agricultural Technology, Rajamangala University of Technology Lanna, Chiang Rai, 57120 Chiang Rai (Thailand); Whitlow, Harry J. [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland)

    2015-04-01

    There a disparity between the way the resolution is specified in microscopy and lithography using light compared to MeV ion microscopy and lithography. In this work we explore the implications of the way the resolution is defined with a view to answering the questions; how are the resolving powers in MeV ion microscopy and lithography relate to their optical counterparts? and how do different forms of point spread function affect the modulation transfer function and the sharpness of the edge profile?.

  19. Linac4 crosses the 100 MeV threshold

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    The new linear accelerator, which from 2020 will be the first link in the accelerator chain, has entered a new stage of its commissioning.   Members of the team in charge of the commissioning of Linac4 in the accelerator’s control room. A few hours earlier, Linac4 accelerated a beam to 107 MeV for the first time. We couldn’t have imagined a more appropriate date: on 1 July (1.07), Linac4 reached an energy of 107 MeV. Having crossed the 100 MeV barrier, the linear accelerator is now on the home straight of its commissioning. “This stage was very quick – it took less than two weeks,” says Alessandra Lombardi, deputy project leader of Linac4, in charge of the commissioning. In 2020, Linac4 will replace the existing Linac2 as the first link in the accelerator chain. It will accelerate beams of H- ions (protons surrounded by two electrons) to 160 MeV, compared to 50 MeV with Linac2. The new machine is particularly sophisticated as it comprises...

  20. History of the ZGS 500 MeV booster.

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.; Martin; R.; Kustom, R.

    2006-05-09

    The history of the design and construction of the Argonne 500 MeV booster proton synchrotron from 1969 to 1982 is described. This accelerator has since been in steady use for the past 25 years to power the Argonne Intense Pulsed Neutron Source (IPNS).

  1. Magnifying lens for 800 MeV proton radiography.

    Science.gov (United States)

    Merrill, F E; Campos, E; Espinoza, C; Hogan, G; Hollander, B; Lopez, J; Mariam, F G; Morley, D; Morris, C L; Murray, M; Saunders, A; Schwartz, C; Thompson, T N

    2011-10-01

    This article describes the design and performance of a magnifying magnetic-lens system designed, built, and commissioned at the Los Alamos National Laboratory (LANL) for 800 MeV flash proton radiography. The technique of flash proton radiography has been developed at LANL to study material properties under dynamic loading conditions through the analysis of time sequences of proton radiographs. The requirements of this growing experimental program have resulted in the need for improvements in spatial radiographic resolution. To meet these needs, a new magnetic lens system, consisting of four permanent magnet quadrupoles, has been developed. This new lens system was designed to reduce the second order chromatic aberrations, the dominant source of image blur in 800 MeV proton radiography, as well as magnifying the image to reduce the blur contribution from the detector and camera systems. The recently commissioned lens system performed as designed, providing nearly a factor of three improvement in radiographic resolution.

  2. First Light: MeV Astrophysics from the Moon

    Science.gov (United States)

    Miller, Richard S.; Lawrence, David J.

    2016-06-01

    We report evidence of the first astrophysical source detected from the Moon at MeV energies. Our detection of Cygnus X-1 is a validation of a new investigative paradigm in which the lunar environment is intrinsic to the detection approach: the Lunar Occultation Technique (LOT). NASA’s Lunar Prospector mission served as a proxy for a dedicated LOT-based mission. The characteristic signature of temporal modulation, generated by repeated lunar occultations and encoded within acquired gamma-ray data (0.5-9 MeV), is consistent with an unambiguous detection of Cygnus X-1 at 5.4σ significance. Source localization and long-term monitoring capabilities of the LOT are also demonstrated. This “first light” detection verifies the basic tenets of the LOT methodology, reinforces its feasibility as an alternative astronomical detection paradigm for nuclear astrophysics investigations, and is an illustration of the fundamental benefits of the Moon as a platform for science.

  3. Determination of the neutron capture cross sections of 232Th at 14.1 MeV and 14.8 MeV using the neutron activation method

    CERN Document Server

    Lan, Chang-Lin; Peng, Meng; Lv, Tao; Yao, Ze-en; Chen, Jin-Gen; Kong, Xiang-Zhong

    2016-01-01

    The 232Th(n,{\\gamma})233Th neutron capture reaction cross sections were measured at average neutron energies of 14.1 MeV and 14.8 MeV using the activation method. The neutron flux was determined using the monitor reaction 27Al(n,{\\alpha})24Na. The induced gamma-ray activities were measured using a low background gamma ray spectrometer equipped with a high resolution HPGe detector. The experimentally determined cross sections were compared with the literatures data, evaluated data of ENDF/B-VII, JENDL-4.0, and CENDL-3.1. The Excitation functions of 232Th(n,{\\gamma}) reaction were also calculated theoretically using the TALYS 1.6 computer code.

  4. Evolution of the 400 MeV linac design

    Energy Technology Data Exchange (ETDEWEB)

    MacLachlan, J.A.

    1987-11-09

    The basic premises of the conceptual design for the linac upgrade are pursued to establish lengths, gradients, power dissipation, etc., for the 400 MeV linac and matching section. The discussion is limited to accelerating and focusing components. Wherever values depend on the choice of the accelerating structure, the disk-and-washer structure is emphasized; the results are generally relevant to the side coupled cavity choice also.

  5. Construction of a pulsed MeV positron beam line

    Energy Technology Data Exchange (ETDEWEB)

    Masuno, Shin-ichi; Okada, Sohei; Kawasuso, Atsuo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    To develop a fast (1 MeV) and short pulsed (100 ps) positron beam which enables defect behavior analysis of bulk states of materials even at high temperatures where a usual positron source would melt, we have been performing design study and construction of the beam line in a three-year program since 1994. This report describes the components, design study results and experimental results of the completed parts until now. (author)

  6. RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS

    Energy Technology Data Exchange (ETDEWEB)

    Zeller, A.F.; Ronningen, R.M.; Godeke, A.; Heilbronn, L.H.; McMahan-Norris, P.; Gupta, R.

    2007-11-27

    The use of HTS materials in high radiation environmentsrequires that the superconducting properties remain constant up to aradiation high dose. BSCCO-2223 samples from two manufacturers wereirradiated with 50 MeV protons at fluences of up to 5 x 1017 protons/cm2.The samples lost approximately 75 percent of their pre-irradiation Ic.This compares with Nb3Sn, which loses about 50 percent at the samedisplacements per atom.

  7. RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS

    Energy Technology Data Exchange (ETDEWEB)

    Zeller, A.F.; Ronningen, R.M.; Godeke, Arno; Heibronn, L.H; McMahan-Norris, P.; Gupta, R.

    2007-11-01

    The use of HTS materials in high radiation environments requires that the superconducting properties remain constant up to a radiation high dose. BSCCO-2223 samples from two manufacturers were irradiated with 50 MeV protons at fluences of up to 5 x 10{sup 17} protons/cm{sup 2}. The samples lost approximately 75% of their pre-irradiation I{sub c}. This compares with Nb{sub 3}Sn, which loses about 50% at the same displacements per atom.

  8. Status of the 1 MeV Accelerator Design for ITER NBI

    Science.gov (United States)

    Kuriyama, M.; Boilson, D.; Hemsworth, R.; Svensson, L.; Graceffa, J.; Schunke, B.; Decamps, H.; Tanaka, M.; Bonicelli, T.; Masiello, A.; Bigi, M.; Chitarin, G.; Luchetta, A.; Marcuzzi, D.; Pasqualotto, R.; Pomaro, N.; Serianni, G.; Sonato, P.; Toigo, V.; Zaccaria, P.; Kraus, W.; Franzen, P.; Heinemann, B.; Inoue, T.; Watanabe, K.; Kashiwagi, M.; Taniguchi, M.; Tobari, H.; De Esch, H.

    2011-09-01

    The beam source of neutral beam heating/current drive system for ITER is needed to accelerate the negative ion beam of 40A with D- at 1 MeV for 3600 sec. In order to realize the beam source, design and R&D works are being developed in many institutions under the coordination of ITER organization. The development of the key issues of the ion source including source plasma uniformity, suppression of co-extracted electron in D beam operation and also after the long beam duration time of over a few 100 sec, is progressed mainly in IPP with the facilities of BATMAN, MANITU and RADI. In the near future, ELISE, that will be tested the half size of the ITER ion source, will start the operation in 2011, and then SPIDER, which demonstrates negative ion production and extraction with the same size and same structure as the ITER ion source, will start the operation in 2014 as part of the NBTF. The development of the accelerator is progressed mainly in JAEA with the MeV test facility, and also the computer simulation of beam optics also developed in JAEA, CEA and RFX. The full ITER heating and current drive beam performance will be demonstrated in MITICA, which will start operation in 2016 as part of the NBTF.

  9. Target irradiation facility and targetry development at 160 MeV proton beam of Moscow linac

    CERN Document Server

    Zhuikov, B L; Konyakhin, N A; Vincent, J

    1999-01-01

    A facility has been built and successfully operated with the 160 MeV proton beam of Moscow Meson factory LINAC, Institute for Nuclear Research (INR) of Russian Academy of Science, Troitsk. The facility was created for various isotope production goals as well as for fundamental nuclear investigations at high intensity beam (100 mu A and more). An important part of the facility targetry system is a high-intensity beam monitoring collimator device. Measurements of the temperature distribution between collimator sectors, cooling water flow and temperature, and the beam current, provide an opportunity to compute beam losses and beam position. The target holder design allows easy insertion by manipulator and simultaneous bombardment of several different targets of various types and forms, and variation of proton energy on each target over a wide range below 160 MeV. The main target utilized for commercial sup 8 sup 2 Sr isotope production is metallic rubidium in a stainless-steel container. A regular wet chemistry ...

  10. Response of Inorganic Scintillators to Neutrons of 3 and 15 MeV Energy

    CERN Document Server

    Lucchini, M; Pizzichemi, M; Chipaux, R; Jacquot, F; Mazue, H; Wolff, H; Lecoq, P; Auffray, E

    2014-01-01

    In the perspective of the development of future high energy physics experiments, homogeneous calorimeters based on inorganic scintillators can be considered for the detection of hadrons (e.g., calorimeter based on dual-readout technique). Although of high importance in the high energy physics framework as well as for homeland security applications, the response of these inorganic scintillators to neutrons has been only scarcely investigated. This paper presents results obtained using five common scintillating crystals (of size around 2x2x2 cm 3), namely lead tungstate (PbWO4), bismuth germanate (BGO), cerium fluoride (CeF3), Ce-doped lutetium-yttrium orthosilicate (LYSO:Ce) and lutetium aluminum garnet (LuAG:Ce) in a pulsed flux of almost mono-energetic (similar to 3 MeV and similar to 15 MeV) neutrons provided by the Van de Graff accelerator SAMES of CEA Valduc. Energy spectra have been recorded, calibrated and compared with Geant4 simulations computed with different physics models. The neutron detection eff...

  11. Local and global nucleon optical models from 1 keV to 200 MeV

    CERN Document Server

    Köning, A J

    2003-01-01

    We present new phenomenological optical model potentials (OMPs) for neutrons and protons with incident energies from 1 keV up to 200 MeV, for (near-)spherical nuclides in the mass range 24<=A<=209. They are based on a smooth, unique functional form for the energy dependence of the potential depths, and on physically constrained geometry parameters. For the first time, this enables one to predict basic scattering observables over a broad mass range and over an energy range that covers several orders of magnitude in MeV. Thereby, the necessity of using different OMPs in different energy regions has been removed. Using extensive grid searches and a new computational steering technique, we have obtained optical model parameters for many isotopes separately. We recommend that the resulting, so-called local, optical models be used in theoretical analyses of nuclear data. From these parameterizations, we have also constructed asymmetry-dependent neutron and proton global OMPs that are superior to all other exi...

  12. Neutron-induced fission cross section of 242Pu from 15 MeV to 20 MeV

    Directory of Open Access Journals (Sweden)

    Jovančević N.

    2017-01-01

    Full Text Available Accurate nuclear-data needs in the fast-neutron-energy region have been recently addressed for the development of next generation nuclear power plants (GEN-IV by the OECD Nuclear Energy Agency (NEA. This sensitivity study has shown that of particular interest is the 242Pu(n,f cross section for fast reactor systems. Measurements have been performed with quasi-monoenergetic neutrons in the energy range from 15 MeV to 20 MeV produced by the Van de Graaff accelerator of the JRC-Geel. A twin Frisch-grid ionization chamber has been used in a back-to-back configuration as fission fragment detector. The 242Pu(n,f cross section has been normalized to 238U(n,f cross section data. The results were compared with existing literature data and show acceptable agreement within 5%.

  13. A dynamic programming approach for quickly estimating large network-based MEV models

    DEFF Research Database (Denmark)

    Mai, Tien; Frejinger, Emma; Fosgerau, Mogens

    2017-01-01

    by a rooted, directed graph where each node without successor is an alternative. We formulate a family of MEV models as dynamic discrete choice models on graphs of correlation structures and show that the dynamic models are consistent with MEV theory and generalize the network MEV model (Daly and Bierlaire...

  14. First H- beam accelerated at Linac4: 3MeV done, 157 MeV to go!

    CERN Multimedia

    Linac4 Project Team

    2013-01-01

    On 14 November, the first H- (one proton surrounded by two electrons) beam was accelerated to the energy of 3 MeV in the Linac4 - the new linear accelerator that will replace Linac2 as low-energy injector in the LHC accelerator chain.      A view of the Linac4 taken during the recent tests (top image) and the current measured by the instruments at the end of the acceleration line on 14 November (bottom image). Images: Linac4 collaboration. Using the recently installed Radio Frequency Quadrupole (RFQ) accelerator, 13 mA of current were accelerated to the energy of 3 MeV. After the successful commissioning of the Linac4 RFQ at the 3 MeV test stand completed during the first months of 2013, the whole equipment (composed of the RFQ itself, the following Medium Energy Beam Transport line and its diagnostic line) were moved to the Linac4 tunnel during summer and installed in their final position. In the meantime, a new ion source was assembled, installed and successfu...

  15. 500-MeV electron beam bench-mark experiments and calculations

    Energy Technology Data Exchange (ETDEWEB)

    Farley, E.; Crase, K.; Selway, D.

    1979-12-01

    Experiments measuring the energy deposited by electron beams were performed to provide bench marks against which to evaluate our HANDYL76 electron beam computer code. The experiments, done at Stanford's Mk III accelerator, measured dose vs depth and dose vs radius profiles induced in layered aluminum targets by 500-MeV electrons. The dose was measured by passive thermoluminescence and photographic film placed between aluminum plates. The calculations predict a dose vs radius profile that forward-peaks on axis after the beam passes through a 200-cm air gap; the experimental measurements do not show this peak. This discrepancy indicates there may be a problem in using HANDYL76 to calculate deep penetration of a target with a large gap.

  16. Annealing behaviour of MeV erbium implanted lithium niobate

    Energy Technology Data Exchange (ETDEWEB)

    Gortmaker, P.; McCallum, J.C. [Royal Melbourne Inst. of Tech., VIC (Australia)

    1993-12-31

    Lithium niobate (LiNbO{sub 3}) is a crystalline ceramic commonly used in the fabrication of optoelectronic devices. Recently, rare earth doping of LiNbO{sub 3} has become a topic of particular interest. The electronic configuration of rare earth elements such as Erbium (Er) and Neodymium (Nd) allows them to lase in nearly any host matrix making fabrication of a whole range of new optoelectronic devices possible. At present, the doping technique, for LiNbO{sub 3} are centred upon diffusion technology, but the diffusion profiles for the rare earths are not generally well-matched to the optical modes of the device. The aim of this research is to develop MeV implantation and annealing conditions of rare earth doped LiNbO{sub 3} that would be compatible with optoelectronic device fabrication. To determine the characteristics of the rare earth elements in the LiNbO{sub 3} host material over the depth range of interest in optoelectronic device applications, high energy Rutherford backscattering spectrometry and ion channeling (RBS-C) must be used. Presented here are the Er depth profile and lattice damage results obtained from 5 MeV RBS-C measurements on samples of LiNbO{sub 3} implanted with various doses of MeV Erbium and subsequently thermally annealed at a temperature of 1000 deg C. It was found that there is a peak implant concentration (2 x 10{sup 16} Er/cm{sup 2}) for which erbium no longer goes substitutional in the lattice, and the implantation damage is not fully removed by annealing. 8 refs., 3 figs.

  17. An intense 14 MeV neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Su Tongling; Sun Biehe; Yang Baotai; Piao Yubo; Shui Yongqing; Chen Kefan; Wang Xuezhi; Yang Cheng; Niu Zhanqi; Liu Yanton; Pan Minshen; Hong Zhongti; Chen Qin (Lanzhou Univ., GS (China). Inst. of Nuclear Research)

    1990-02-15

    A 3x10{sup 12} n/s source of 14 MeV neutrons is described in this paper. The neutrons are produced by the T(d,n){sup 4}He reaction under a 30 mA, 300 keV deuteron beam bombarding a water-cooled, rotating titanium-tritide target. The size of the beam spot on the target is 1.8 cm, and at the distance of closest approach to the source a neutron flux of 5x10{sup 11} n/cm{sup 2} s is obtained. (orig.).

  18. Polarization Observables in Deuteron Photodisintegration below 360 MeV

    CERN Document Server

    Glister, J; Lee, B W; Gilman, R; Sarty, A J; Strauch, S; Higinbotham, D W; Piasetzky, E; Allada, K; Armstrong, W; Arrington, J; Beck, A; Benmokhtar, F; Berman, B L; Boeglin, W; Brash, E; Camsonne, A; Calarco, J; Chen, J P; Choi, Seonho; Chudakov, E; Coman, L; Craver, B; Cusanno, F; Dumas, J; Dutta, C; Feuerbach, R; Freyberger, A; Frullani, S; Garibaldi, F; Hansen, J -0; Holmstrom, T; Hyde, C E; Ibrahim, H; Ilieva, Y; de Jager, C W; Jiang, X; Jones, M K; Kang, H; Kelleher, A; Khrosinkova, E; Kuchina, E; Kumbartzki, G; LeRose, J J; Lindgren, R; Markowitz, P; Beck, S May-Tal; McCullough, E; Meekins, D; Meziane, M; Meziani, Z -E; Michaels, R; Moffit, B; Norum, B E; Oh, Y; Olson, M; Paolone, M; Paschke, K; Perdrisat, C F; Potokar, M; Pomatsalyuk, R; Pomerantz, I; Puckett, A; Punjabi, V; Qian, X; Qiang, Y; Ransome, R; Reyhan, M; Roche, J; Rousseau, Y; Saha, A; Sawatzky, B; Schulte, E; Shabestari, M; Shahinyan, A; Shneor, R; Sirca, S; Slifer, K; Solvignon, P; Song, J; Sparks, R; Subedi, R; Urciuoli, G M; Wang, K; Wojtsekhowski, B; Yan, X; Yao, H; Zhan, X; Zhu, X

    2010-01-01

    High precision measurements of induced and transferred recoil proton polarization in d(polarized gamma, polarized p})n have been performed for photon energies of 277--357 MeV and theta_cm = 20 degrees -- 120 degrees. The measurements were motivated by a longstanding discrepancy between meson-baryon model calculations and data at higher energies. At the low energies of this experiment, theory continues to fail to reproduce the data, indicating that either something is missing in the calculations and/or there is a problem with the accuracy of the nucleon-nucleon potential being used.

  19. Radiation Monitoring System of 30 MeV Cyclotron

    Science.gov (United States)

    Lee, Jin-Woo; Hur, Min-Goo; Jeong, Gyosung; Kim, Jongil

    2017-09-01

    A state-of-the-art radiation monitoring system was implemented at KAERI for a 30-MeV cyclotron. This system consists of several types of radiation measuring systems for ambient dose equivalent rate measurements of outside photon and neutron areas as well as inside the cyclotron, and monitors the alpha and beta particulates released from a stack, as well as the results of worker contamination at the portal of the cyclotron. In addition, an automatic alarm system is also mounted if there are alarms in the measuring systems.

  20. Shielding variation effects for 250 MeV protons on tissue targets.

    Science.gov (United States)

    Brandl, A; Hranitzky, C; Rollet, S

    2005-01-01

    This paper provides results of computer simulation studies with the goal to analyse issues regarding radiation protection for personnel, patients and third persons involved in hadron therapy treatment. The treatment room and the patient are modelled by simple cylindrical geometries at incident proton energies of 250 MeV. Monte Carlo simulations of the energy and angular dependence of proton, neutron and photon radiation fields and resulting ambient dose equivalent distributions outside the shielding walls are performed. In order to investigate systematic uncertainties due to the shielding materials and inherent to the computer models, various concrete compositions, densities and water contents are modelled, and the influence of simulation parameters on the results obtained is determined. Generally, good agreement is found between results provided by MCNPX and FLUKA computer codes. Variations in neutron ambient dose attenuation from -50 to +/-30% are found due to varying concrete composition. Changes in the water content of the concrete in the order of 8% may cause variations up to 20%.

  1. Angular spreading measurements using MeV ion microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Whitlow, Harry J., E-mail: harry.whitlow@he-arc.ch [Institut des Microtechnologies Appliquées, Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Department of Physics, P.O. Box 35 (YFL), FI-40014 University of Jyväskylä (Finland); Ren, Minqin; Chen, Xiao; Osipowicz, Thomas; Kan, Jeroen A. van; Watt, Frank [Centre for Ion Beam Applications, National University of Singapore (Singapore)

    2013-07-01

    The sharpness of MeV ion microscope images is governed by small-angle scattering and associated lateral spreading of the ion beam in the sample. We have investigated measurement of the half-angle of the angular spreading distribution by characterising the image blurring in direct-Scanning Transmission Ion Microscopy (direct-STIM). In these tests Mylar™ foils of 0.5–6 μm were used to induce angular spreading. Images were taken of an electron microscope grid using 2 MeV protons with, and without, the foils in the beam path. The blurring was measured by fitting the width of a circular Gaussian point spread function to the images with and without the foil in position. The results show the half-angle width of the spreading has a square root dependence on foil thickness that lies intermediate between SRIM predictions and the theoretical estimates (Bird and Williams fits to the Sigmund and Winterbon data and Amsel et al.)

  2. Limitations of 14 MeV neutron simulation techniques

    Science.gov (United States)

    Kley, W.; Bishop, G. R.; Sinha, A.

    1988-07-01

    A D-T fusion cycle produces five times more neutrons per unit of energy released than a fission cycle, with about twice the damage energy and the capability to produce ten times more hydrogen, helium and transmutation products than fission neutrons. They determine, together with other parameters, the lifetime of the construction materials for the low plasma-density fusion reactors (tokamak, tandem-mirror, etc.), which require a first wall. For the economie feasibility of fusion power reactors the first wall and blanket materials must withstand a dose approaching 300 to 400 dpa. Arguments are presented that demonstrate that today's simulation techniques using existing fission reactors and charged particle beams are excellent tools to study the underlying basic physical phenomena of the evolving damage structures but are not sufficient to provide a valid technological data base for the design of economie fusion power reactors. It is shown than an optimized spallation neutron source based on a continuous beam of 600 MeV, 6 mA protons is suitable to simulate first wall conditions. Comparing it with FMIT the 35 MeV, 100 mA D + -Li neutron source, we arrive at the following figure of merit: FM = {(dpa·volume) EURAC}/{(dpa·volume) FMIT} = {} = 111 reflecting the fact that the proton beam generates about 100 times more neutrons than the deuteron beam in FMIT for the same beam power.

  3. (π+/-,π+/-p) reaction at 245 MeV

    Science.gov (United States)

    Piasetzky, E.; Ashery, D.; Altman, A.; Yavin, A. I.; Schlepütz, F. W.; Powers, R. J.; Bertl, W.; Felawka, L.; Walter, H. K.; Winter, R. G.; Pluym, J. V. D.

    1982-05-01

    The inclusive (π+/-,π+/-p) reactions on C, Fe, and Bi were studied at 245 MeV in a broad kinematic range by means of coincidence measurement of the outgoing particles. The π-p angular correlations and proton-energy spectra show features consistent with those expected from quasifree scattering. It is observed that about 80% of the inclusive inelastic scattering cross section at backward pion angles may be attributed to nucleon knockout mechanisms. The results allow identification of the direct quasifree process, unperturbed by higher order effects, which accounts for 30%, 20%, and 15% of the C, Fe, and Bi inclusive (π+,π+) differential cross sections, respectively. The ratio of positive to negative pion cross sections for quasifree scattering, integrated over the proton energy and angle, are in agreement with the ratio for free π-p scattering. Such is not the case for various proton angles. The deviation of the positive to negative ratio at the peak of the proton angular correlation from the free scattering ratio is most pronounced for more forward pion angles. NUCLEAR REACTIONS (π+/-,π+/-p) coin. measurements on C, Fe, Bi, E=245 MeV; deduced σknockout decomposition of σinelastic.

  4. Characteristic parameters of 6--21 MeV electron beams from a 21 MeV linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghazi, M.S.A.L. (Department of Medical Physics, Thunder Bay Regional Cancer Centre, Ontario Cancer Treatment and Research Foundation, Thunder Bay, Ontario P7A 7T1, (Canada) Department of Physics, Lakehead University, Thunder Bay, Ontario P7B 5E1, (Canada) Lingman, D. Department of Medical Physics, Thunder Bay Regional Cancer Centre, Ontario Cancer Treatment and Research Foundation, Thunder Bay, Ontario P7A 7T1, (Canada) Department of Computer Science, Lakehead University, Thunder Bay, Ontario P7B 5E1, (Canada)); Gilbert, L.D. (Thekkumthala, J. Department of Medical Physics, Thunder Bay Regional Cancer Centre, Ontario Cancer Treatment and Research Foundation, Thunder Bay, Ontario P7A 7T1, (Canada))

    1991-07-01

    Dosimetry measurements have been carried out for the electron beams produced by a linear accelerator at energies 6, 8, 10, 14, 18, and 21 MeV. Characteristic parameters of the central axis dose distributions were derived and compared to corresponding values of electron beams from other accelerators in clinical use where such a comparison is appropriate. A comprehensive set of dosimetric parameters is provided for electron beam treatment planning. The data include central axis depth dose, range--energy parameters, beam penumbra and uniformity.

  5. Temperature Dependence of the Primary Species Yields of Liquid Water Radiolysis by 0.8-MeV Fast Neutrons

    Directory of Open Access Journals (Sweden)

    S.L. Butarbutar

    2016-04-01

    Full Text Available The yields of species such as e-aq, H•, •OH, H2 and H2O2, formed from the radiolysis of neutral liquid water by the incidence of 0.8-MeV neutrons at temperatures between 25 and 350°C, were calculated by using Monte Carlo simulations. The slowing down of these neutrons through elastic scattering produced recoil protons elastically of ~0.5057, 0.186, and 0.0684 MeV which had linear energy transfers (LETs of ~40, 67 and 76 keV/µm, respectively, at 25°C. The effects of neutron radiation can be predicted based on the contribution of those first three recoil protons by neglecting the radiation effects due to oxygen ion recoils. Then, the fast neutron yields could be estimated by summing the yields of contributing protons after corresponding weightings were used according to their energy. In this work, yields were calculated at 10-7 and 10-6 s after incidence of neutron radiation in water at the aforementioned temperature range. Overall, there is a reasonably good agreement between our calculated and existing experimental G-values for the entire temperature range. However, we proposed an hypothesis that the not very significant difference between experimental data and our calculated data is due to the different measuring time used in obtaining the experimental data as compared to the ones used in our calculation. Our computed yields for 0.8-MeV fast neutron radiation show an essentially similar temperature dependences over the range of temperature studied with 2-MeV fast neutron and low-LET radiation, but with lower values for yields of free radicals and higher values for molecular yields.

  6. Proton Polarimeter Calibration between 82 and 217 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Glister, J; Lee, B; Beck, A; Brash, E; Camsonne, A; Choi, S; Dumas, J; Feuerbach, R; Gilman, R; Higinbotham, D W; Jiang, X; Jones, M K; May-Tal Beck, S; McCullough, E; Paolone, M; Piasetzky, E; Roche, J; Rousseau, Y; Sarty, A J; Sawatzky, B; Strauch, S

    2009-07-01

    The proton analyzing power in carbon has been measured for energies of 82 to 217 MeV and proton scattering angles of 5 to 41 degrees. The measurements were carried out using polarized protons from the elastic scattering H(pol. e, pol. p) reaction and the Focal Plane Polarimeter (FPP) in Hall A of Jefferson Lab. A new parameterization of the FPP p-C analyzing power was fit to the data, which is in good agreement with previous parameterizations and provides an extension to lower energies and larger angles. The main conclusions are that all polarimeters to date give consistent measurements of the carbon analyzing power, independently of the details of their construction and that measuring on a larger angular range significantly improves the polarimeter figure of merit at low energies.

  7. The 5 MeV bump - a nuclear whodunit mystery

    CERN Document Server

    Huber, Patrick

    2016-01-01

    We perform a combined analysis of recent NEOS and Daya Bay data on the reactor antineutrino spectrum. This analysis includes approximately 1.5 million antineutrino events, which is the largest neutrino event sample analyzed to date. We use a double ratio which cancels flux model dependence and related uncertainties as well as the effects of the detector response model. We find at 3-4 standard deviation significance level, that plutonium-239 and plutonium-241 are disfavored as the single source for the the so-called 5 MeV bump. This analysis method has general applicability and in particular with higher statistics data sets will be able to shed significant light on the issue of the bump. With some caveat this also should allow to improve the sensitivity for sterile neutrino searches in NEOS.

  8. Multipole Stack for the 800 MeV PS Booster

    CERN Multimedia

    1975-01-01

    The 800 MeV PS Booster had seen first beam in its 4 superposed rings in 1972, routine operation began in 1973. In the strive for ever higher beam intensities, the need for additional multipole lenses became evident. After detailed studies, the manufacture of 8 stacks of multipoles was launched in 1974. Each stack consists of 4 superposed multipoles and each multipole has 4 concentric shells. From the innermost to the outermost shell, Type A contains octupole, skew-octupole, sextupole, skew-sextupole. Type B contains skew-octupole, skew-sextupole, vertical dipole, horizontal dipole. Completion of installation in 1976 opened the way to higher beam intensities. M. Battiaz is seen here with a multipole stack and its many electrical connections.

  9. Two charmoniumlike charged axial resonances near 3885 MeV

    CERN Document Server

    Voloshin, M B

    2016-01-01

    It is argued that the charged $Z^+_c(3885)$ resonance, treated as a `molecular' state of charmed $D$ and $D^*$ mesons, is likely to consist of two peaks unequally coupled to the $D^{*+} \\bar D^0$ and $D^+ \\bar D^{*0}$ channels. The peaks should be split in mass by at least approximately 1.5 MeV. This behavior arises from an enhancement of the effect of isospin violation in the masses of the $D$ and $D^*$ mesons due to apparent suppression of forces between the mesons depending on the spins of the heavy as well as of the light quarks. The suggested double-peak structure can be studied either by direct shape measurement in the channels with heavy mesons, or by isospin-violating transitions from $Z_c^\\pm(3885)$ to the states of charmonium plus a light meson.

  10. Focussed MeV ion beam implanted waveguides

    Energy Technology Data Exchange (ETDEWEB)

    Von Bibra, M.L.; Roberts, A.; Nugent, K.; Jamieson, D.N. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Single mode buried optical waveguides have been fabricated in fused silica by MeV proton implantation using a focussed hydrogen ion beam. The technique has the potential to direct write waveguide devices and produce multi-layered structures, without the need for intermediate steps such as mask fabrication or layered depositions. A micron resolution Confocal Raman Spectrometer has been used to map the distribution of atomic vacancies that forms the waveguiding region. The results are compared with theoretical calculations. Losses of 3 dB cm{sup -1} have been measured in unannealed samples, which decreases to less than 0.5 dB cm{sup -1} after annealing at 500 degrees Celsius. We describe methods for determining the refractive index distribution of single mode buried waveguides from their output intensity distributions via an inversion of the scalar wave equation. (authors). 5 figs.

  11. Design of 10 MeV cyclotron accelerator

    Directory of Open Access Journals (Sweden)

    R Solhju

    2015-09-01

    Full Text Available Design and construction of 10MeV cyclotron has been started at Amirkabir University of Technology since 2012. So far, the conceptual and detail engineering design phases have been finalized. The main purpose of this baby cyclotron is to generate proton beam for the production of PET radioisotopes. The cyclotron consists of magnet, cavity, ion source, RF and LLRF system, vacuum system, cooling system, power amplifiers and power supplies system. In this paper, a brief of design principles for all the parts of cyclotron and their final simulation results is presented. It should be noted that these simulations have been performed and optimized by the most accurate softwares such as TOSCA, ANSYS, HFSS, SolidWorks and CST. Also, the manufacturing feasibility of all the parts is performed and their dimensions and parameters are synchronized with manufacturing standards

  12. Shielding measurements for a 230 MeV proton beam

    Energy Technology Data Exchange (ETDEWEB)

    Siebers, J.V.

    1990-01-01

    Energetic secondary neutrons produced as protons interact with accelerator components and patients dominate the radiation shielding environment for proton radiotherapy facilities. Due to the scarcity of data describing neutron production, attenuation, absorbed dose, and dose equivalent values, these parameters were measured for 230 MeV proton bombardment of stopping length Al, Fe, and Pb targets at emission angles of 0{degree}, 22{degree}, 45{degree}, and 90{degree} in a thick concrete shield. Low pressure tissue-equivalent proportional counters with volumes ranging from 1 cm{sup 3} to 1000 cm{sup 3} were used to obtain microdosimetric spectra from which absorbed dose and radiation quality are deduced. Does equivalent values and attenuation lengths determined at depth in the shield were found to vary sharply with angle, but were found to be independent of target material. Neutron dose and radiation length values are compared with Monte Carlo neutron transport calculations performed using the Los Alamos High Energy Transport Code (LAHET). Calculations used 230 MeV protons incident upon an Fe target in a shielding geometry similar to that used in the experiment. LAHET calculations overestimated measured attenuation values at 0{degree}, 22{degree}, and 45{degree}, yet correctly predicted the attenuation length at 90{degree}. Comparison of the mean radiation quality estimated with the Monte Carlo calculations with measurements suggest that neutron quality factors should be increased by a factor of 1.4. These results are useful for the shielding design of new facilities as well as for testing neutron production and transport calculations.

  13. Conceptual Design Study of 13 MeV Proton Cyclotron

    Directory of Open Access Journals (Sweden)

    Silakhuddin

    2012-04-01

    Full Text Available A study to determine the conceptual design of a 13 MeV proton cyclotron for PET (Positron Emission Tomography facility has been carried out. Based on studies on reactions of PET radioisotopes production, reaction cross-sections and some design references, a design of the proton cyclotron is proposed. The design criteria for the main components are decided using empirical and semitheoretical methods, as well as by referring to data regarding cyclotrons for PET production. The empirical method was carried out by using some data from operational experiences of BATAN cyclotron at Serpong, while the semitheoretical method was carried out by using the commonly used equations of cyclotron basic theory. The general layout of components and the main components, namely the ion source, the RF dees, the magnet, and the extractor are discussed. Based on the calculations and on the data used, the cyclotron is designed as a negative ion acceleration cyclotron with internal ion source. The designated proton energy and beam currents are 13 MeV and 50 µA. Its magnetic field is in the relativistic mode with sectors on the pole. The magnetic field intensity at the extraction radius is 12.745 kG and in the innermost radius is 12.571 kG. The magnetic poles consist of four sectors to make adequate space for components placement such as dees, ion source, extractor and beam probe. The dee angle is 430. The dee operates at 78 MHz on the fourth harmonic. A multifoil extractor is chosen to obtain an efficient operation

  14. Neutron-induced fission cross sections of uraniums up to 40 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus); Hasegawa, A.

    1998-11-01

    Statistical theory of nuclear reactions, well-proved below 20 MeV, is applied for {sup 235}U and {sup 238}U fission data analysis up to {approx}40 MeV. It is shown that measured data could be reproduced. Chance structure of measured fission cross section is provided, it`s validity is supported by description of data for competing (n,xn)-reactions. Role of fissility of target nucleus is addressed. It seems that gap in incident neutron energy interval of 20 MeV - 50 MeV, below which evaluation approaches are well-developed, and above which simplified statistical approaches are valid, could be covered. (author)

  15. Backward Secondary Electron Emission Yield of Thick Targets Induced by MeV Ions

    Institute of Scientific and Technical Information of China (English)

    JIANG Lei; ZHAO Guo-Qing; ZHOU Zhu-Ying

    2000-01-01

    The backward secondary electron emission yields of MeV ions (H+, He+, He++, Cl, Si, and Cu ) impinging on thick carbon and gold targets are studied. The measured results for H+ (1MeV ≤ E ≤ 5MeV) on carbon are proportional to the electronic stopping power. Our experimental data and fitting formula of yields for H+ (1 MeV≤ E≤ 4.5MeV) impacting Au are compared with the theoretical expectation. The influence of the collective field and the charge state of ions on the secondary electron emission yield is discussed.

  16. A comparative study of 30MeV boron{sup 4+} and 60MeV oxygen{sup 8+} ion irradiated Si NPN BJTs

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, M. Vinay, E-mail: Vkm288@gmail.com; Krishnaveni, S. [Department of studies in Physics, University of Mysore, Manasagangotri, Mysore 570006 (India); Yashoda, T. [Deparment of Physics, AVK College for women, Hassan-573201 (India); Dinesh, C. M. [Department of Physics, Govt. First grade college for women, Chintamani-563125 (India); Krishnakumar, K. S. [Department of Physics, APS College of Engineering (India); Jayashree, B. [Department of Physics, Maharanis Science College for Women, Bangalore-560001 (India); Ramani [Department of Physics, Bangalore University, Jnanabharathi, Bangalore-560056 (India)

    2015-06-24

    The impact of 30MeV boron{sup 4+} and 60MeV oxygen{sup 8+} ion irradiation on electrical characteristics of 2N3773 Si NPN Bipolar junction transistors (BJTs) is reported in the present study. The transistors were decapped and irradiated at room temperature. Gummel characteristics, DC current gain and Capacitance-voltage (C-V) characteristics were studied before and after irradiation at different fluences. DC current gain has decreased significantly in both boron and oxygen ion irradiation. Also the value of capacitance decreased 3-4 times with increase in fluence. Both 30MeV boron ion and 60MeV oxygen ion induced similar extent of degradation in electrical characteristics of the transistor.

  17. A comparative study of 30MeV boron4+ and 60MeV oxygen8+ ion irradiated Si NPN BJTs

    Science.gov (United States)

    Kumar, M. Vinay; Yashoda, T.; Dinesh, C. M.; Krishnakumar, K. S.; Jayashree, B.; Ramani, Krishnaveni, S.

    2015-06-01

    The impact of 30MeV boron4+ and 60MeV oxygen8+ ion irradiation on electrical characteristics of 2N3773 Si NPN Bipolar junction transistors (BJTs) is reported in the present study. The transistors were decapped and irradiated at room temperature. Gummel characteristics, DC current gain and Capacitance-voltage (C-V) characteristics were studied before and after irradiation at different fluences. DC current gain has decreased significantly in both boron and oxygen ion irradiation. Also the value of capacitance decreased 3-4 times with increase in fluence. Both 30MeV boron ion and 60MeV oxygen ion induced similar extent of degradation in electrical characteristics of the transistor.

  18. M-C simulation of shielding effects of PE, LiH and graphite fibers under 1 MeV electrons and 20 MeV protons

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Shielding effects of different materials under 1 MeV electron and 20 MeV proton beams were simulated with Geant4 code. It was found that shielding effects of polyethylene and graphite fibers are much better than aluminum. Energy depositions in the phantom shielded by the materials are calculated, with the least energy deposition by graphite fiber shielding. The results show that graphite fibers are good radiation shielding material in space programs.

  19. Ultrafast laser driven micro-lens to focus and energy select MeV protons

    Energy Technology Data Exchange (ETDEWEB)

    Toncian, Toma

    2008-05-15

    A technique for simultaneous focusing and energy selection of high-current, MeV proton beams using radial, transient electric fields (10{sup 7}-10{sup 10} V/m) triggered on the inner wall of a hollow micro-cylinder by an intense, sub-picosecond laser-pulse is presented. Due to the transient nature of the radial focusing field, the proposed method allows selection of a desired range out of the spectrum of the poly-energetic proton beam. This technique addresses current drawbacks of laser-accelerated proton beams, i.e. their broad spectrum and divergence at the source. This thesis presents both experimental and computational studies that led to the understanding of the physical processes driving the micro-lens. After an one side irradiation of a hollow metallic cylinder a radial electric field develops inside the cylinder. Hot electrons generated by the interaction between laser pulse and cylinder wall spread inside the cylinder generating a plasma at the wall. This plasma expands into vacuum and sustains an electric field that acts as a collecting lens on a proton beam propagating axially through the cylinder. Both focusing and the reduction of the intrinsic beam divergence from 20 deg to.3 deg for a narrow spectral range was demonstrated. By sub-aperturing the beam a narrow spectral range ({delta}{epsilon}/{epsilon} < 3%) was selected from the poly-energetic beam. The micro-lens properties are tunable allowing for optimization towards applications. Optical probing techniques and proton imaging were employed to study the spacial and temporal evolution of the field and revealed a complex physical scenario of the rise and decay of the radial electric field. Each aspect studied experimentally is interpreted using 2D PIC and ray tracing simulations. A very good agreement between the experimental and computational data is found. The PIC simulations are used to upscale the demonstrated micro-lens capabilities to the focusing of a 270 MeV proton beam, an energy relevant

  20. Measurements of 1.9 MeV electron Bremsstrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Pino, Neivy; Cabal, Fatima Padilla; D' Alessandro, Katia [Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba); Maidana, Nora Lia; Vanin, Vito Roberto; Martins, Marcos Nogueira; Malafronte, Alexandre; Bonini, Alfredo L. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica. Lab. do Acelerador Linear; Sempau, Josep [Universitat Politecnica de Catalunya, Barcelona (Spain)

    2011-07-01

    Full text: Bremsstrahlung Cross section of 1.9 MeV electrons in Ti, Ag, and Au were measured at the Microtron accelerator of the IFUSP. Target mass surface density was in the range 0.1 to 1 mg/cm{sup 2} and the electron current varied from 3 to 30 nA, measured by a Faraday cup. The spectra were measured at three angles (30 deg; 90 deg and 60 deg) using a shielded p-type HPGe detector with an spectroscopy amplifier with pile-up rejection and a fast ADC. A 20 cm in length and 1.2 cm in diameter Pb collimator was placed in front of the detector to reduce the contribution of radiation scattered in the irradiation chamber or other background sources. With the goal of increasing the peak to total gamma-ray efficiency, the collimator hole was placed with its axis parallel to the coaxial detector symmetry axis, but displaced 1.4 cm to the right of the detector crystal axis. Hence, the Ge thickness exposed directly to the Bremsstrahlung beam was about 5 times bigger than that in the crystal axis, where the n-contact hole is located. The detector response functions were obtained by Monte Carlo simulations based on experimentally determined detector dimensions, in a procedure described in a companion paper submitted to this conference (Response function of a p-type Ge detector). Two energy bins: 50 keV and 1 keV were used in the Bremsstrahlung spectrum deconvolution. The first one was employed to determine the energy differential cross section from 0.1 to 1.9 MeV, and the second one for a more specific spectra study, in the high frequency limit or 'tip region'. The experimental spectrum was corrected for pile-up, with a simple model that assumes that the amplifier pile-up rejection resolving time is the same for all measured energies, and the photon background, measured with the target retracted from the beam. The Bremsstrahlung spectra B were obtained as: B = R{sup -}1 X E, where R is the matrix of the detector response function and E the recorded spectrum vector

  1. Collective motion in selected central collisions of Au on Au at 150A MeV

    Science.gov (United States)

    Jeong, S. C.; Herrmann, N.; Fan, Z. G.; Freifelder, R.; Gobbi, A.; Hildenbrand, K. D.; Krämer, M.; Randrup, J.; Reisdorf, W.; Schüll, D.; Sodan, U.; Teh, K.; Wessels, J. P.; Pelte, D.; Trzaska, M.; Wienold, T.; Alard, J. P.; Amouroux, V.; Basrak, Z.; Bastid, N.; Belayev, I. M.; Berger, L.; Bini, M.; Blaich, Th.; Boussange, S.; Buta, A.; Čaplar, R.; Cerruti, C.; Cindro, N.; Coffin, J. P.; Dona, R.; Dupieux, P.; Erö, J.; Fintz, P.; Fodor, Z.; Fraysse, L.; Frolov, S.; Grigorian, Y.; Guillaume, G.; Hölbling, S.; Houari, A.; Jundt, F.; Kecskemeti, J.; Koncz, P.; Korchagin, Y.; Kotte, R.; Kuhn, C.; Ibnouzahir, M.; Legrand, I.; Lebedev, A.; Maguire, C.; Manko, V.; Maurenzig, P.; Mgebrishvili, G.; Mösner, J.; Moisa, D.; Montarou, G.; Montbel, I.; Morel, P.; Neubert, W.; Olmi, A.; Pasquali, G.; Petrovici, M.; Poggi, G.; Rami, F.; Ramillien, V.; Sadchikov, A.; Seres, Z.; Sikora, B.; Simion, V.; Smolyankin, S.; Tezkratt, R.; Vasiliev, M. A.; Wagner, P.; Wilhelmi, Z.; Wohlfarth, D.; Zhilin, A. V.

    1994-05-01

    Using the FOPI facility at GSI Darmstadt complete data of Au on Au collisions at 150A MeV were collected for charged products (Z=1-15) at laboratory angles 1°=3) are used to determine the collective energy which is found to be at least 10A MeV.

  2. Buncher Power Source Monitoring System of 100 MeV Cyclotron

    Institute of Scientific and Technical Information of China (English)

    WEI; Jun-yi; FU; Xiao-liang; GUO; Juan-juan; ZHANG; Yi-wang; CAO; Xue-long; YIN; Zhi-guo; JI; Bin

    2015-01-01

    The 100MeV cyclotron provides 70-100MeV and 200μA proton beam,which can be used in astrophysics,medical,defense,energy and other fields.Buncher system can enhance the beam intensity and expand the scope of application of the accelerator.Buncher system is one part of the

  3. Performance Results of the Modulator for the 100MeV Proton Linac

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Il; Kwon, Hyeok Jung; Kim, Han Sung; Seol, Kyung Tae; Cho, Yong Sub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The modulator for the 100MeV proton linac has been installed at KOMAC (Korea of Multi-purpose Accelerator Complex) site. The specification of modulator is 5.8MW peak power with 1.5ms pulse width, 60Hz repetition rate. There are total 4 sets of modulator for 100-MeV proton linac including 3-MeV RFQ, 20-MeV DTL and 100-MeV DTL. A modulator drives two or three sets of the klystrons simultaneously. After installation and du mmy test of 4 modulators, it has been operated for 100MeV proton linac. In this paper, the performance results of modulators for the 100MeV proton linac are presented. 4 modulators were installed and tested for the 100MeV proton linac. The modulator was measured to have about less than 1% droops at flat top for 500 us pulse by using pulse frequency modulation droop compensation method. The long term voltage variation measurement showed that the voltage increased up to 0.05% for 8 hours. In future, the voltage droop and variation of modulator should be continuously checked in the high repetition rate.

  4. Klystron High Power Operation for KOMAC 100-MeV Proton Linac

    Energy Technology Data Exchange (ETDEWEB)

    Seol, Kyung-Tae; Kim, Seong-Gu; Kwon, Hyeok-Jung; Kim, Han-Sung; Cho, Yong-Sub [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    The Korea multi-purpose accelerator complex (KOMAC) accelerator facility has a 100-MeV proton linac, five beam lines for 20-MeV beam utilization, and another five beam lines for 100-MeV beam utilization. The 100-MeV linac consists of a 50-keV proton injector based on a microwave ion source, a 3-MeV RFQ with a four-vane structure, and a 100-MeV DTL. Nine sets of 1MW klystrons have been operated for the 100-MeV proton linac. The klystron filament heating time was approximately 5700 hours in 2014, and RF operation time was 2863.4 hours. During the high power operation of the klystron, unstable RF waveforms appeared at the klystron output, and we have checked and performed cavity frequency adjustments, magnet and heater current, reflection from a circulator, klystron test without a circulator, and the frequency spectrum measurement. Nine sets of the klystrons have been operated for the KOMAC 100-MeV proton linac. The klystron filament heating time was 5700 hours and RF operation time was 2863.4 hours during the operation in 2014. Some klystrons have unstable RF waveforms at specific power level. We have checked and tested the cavity frequency adjustment, reflection from a circulator, high power test without a circulator, and frequency spectrum at the unstable RF.

  5. Initial Operation Results of the KOMAC 100MeV Proton Linac

    Energy Technology Data Exchange (ETDEWEB)

    Seol, Kyungtae; Kwon, Hyeokjung; Kim, Hansung; Kim, Daeil; Song, Younggi; Cho, Yongsub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The Korea multi-purpose accelerator complex (KOMAC) accelerator facility has a 100-MeV proton linac, five beam lines for 20-MeV beam utilization, and another five beam lines for 100-MeV beam utilization. The 100-MeV linac consists of a 50-keV proton injector based on a microwave ion source, a 3-MeV RFQ with a four-vane structure, and a 100-MeV DTL. The KOMAC started to provide a proton beam to users on July 2013. A 20-MeV beam line and a 100-MeV beam line have been operated for beam service during the first year. In 2013, the proton linac had been operated for more than 2200 hours and beam service time was 432 hours approximately. The accumulated downtime during the first year in 2013 is 94.7 hours and there were some faults at utilities, high voltage modulators, and RF components. The KOMAC started to provide a proton beam to users on July 2013. The proton linac had been operated for more than 2200 hours and beam service time was 432 hours approximately. Accumulated downtime was 94.7 hours and availability was 82 %. The plan for beam power and operation time in 2014 is 10 kW and 2500 hours respectively.

  6. Design of Cavity for 10 MeV Electron Irradiation Accelerator

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    This article describes the 10 MeV high-power electron irradiation accelerator. This accelerator can output varied energy electron beam which the highest energy is 10 MeV or shooting target produce X-rays for industrial radiation processing.

  7. Multipurpose 5-MeV linear induction accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L. Smith, M.W.

    1984-06-11

    Although linear induction accelerators (LIAs) are quite reliable by most standards, they are limited in repeating rate, average power, and reliability because the final stage of energy delivery is based on spark gap performance. In addition, they have a low duty factor of operation. To provide a higher burst rate and greater reliability, the researchers used new technology to develop a magnetic pulse compression scheme that eliminates all spark gaps and exceeds requirements. The paper describes the scheme. The magnetic drive system can be tailored to drive induction cells from a few kA to over 10 kA at 500 kV, with average beam power levels in the megawatts. This new 5-MeV, 2.5-kA LIA under construction at the Lawrence Livermore National Laboratory (LLNL) will be used for the development of high brightness sources and will provide a test bed for the new technology, which should lead to LIAs that surpass the radio frequency linacs for efficiency and reliability, as well as fit other industrial applications, such as sewage sterilization.

  8. Multipurpose 5-MeV linear induction accelerator

    Science.gov (United States)

    Birx, D. L.; Hawkins, S. A.; Poor, S. E.; Reginato, L. L.; Smith, M. W.

    1984-06-01

    Although linear induction accelerators (LIAs) are quite reliable by most standards, they are limited in repeating rate, average power, and reliability because the final stage of energy delivery is based on spark gap performance. In addition, they have a low duty factor of operation. To provide a higher burst rate and greater reliability, new technology was used to develop a magnetic pulse compression scheme that eliminates all spark gaps and exceeds requirements. The magnetic drive system are tailored to drive induction cells from a few kA to over 10 kA at 500 kV, with average beam power levels in the megawatts. This new 5-MeV, 2.5-kA LIA under construction at the Lawrence Livermore National Laboratory (LLNL) will be used for the development of high brightness sources and will provide a test bed for the new technology, which should lead to LIAs that surpass the radio frequency linacs for efficiency and reliability, as well as fit other industrial applications, such as sewage sterilization.

  9. CESAR, 2 MeV electron storage ring.

    CERN Multimedia

    1967-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  10. CESAR, 2 MeV electron storage ring; general view.

    CERN Multimedia

    1964-01-01

    CESAR (CERN Electron Storage and Accumulation Ring) was built as a study-model for the ISR (Intersecting Storage Rings). The model had to be small (24 m circumference) and yet the particles had to be highly relativistic, which led to the choice of electrons. On the other hand, in order to model the behaviour of protons, effects from synchrotron radiation had to be negligible, which meant low magnetic fields (130 G in the bending magnets) and a corresponding low energy of 1.75 MeV. All the stacking (accumulation) procedures envisaged for the ISR were proven with CESAR, and critical aspects of transverse stability were explored. Very importantly, CESAR was the test-bed for the ultrahigh vacuum techniques and components, essential for the ISR, with a final pressure of 6E-11 Torr. The CESAR project was decided early in 1960, design was completed in 1961 and construction in 1963. After an experimental period from 1964 to 1967, CESAR was dismantled in 1968.

  11. Automated Startup of the CEBAF 45 MeV Injector

    Science.gov (United States)

    Kehne, D.; Letta, P.; Dunham, B.; Kazimi, R.

    1997-05-01

    In order to improve the speed and reproducibility of restoring the beam in the CEBAF 45 MeV injector after a full or partial shutdown of the accelerator, a program has been written using the Tcl/Tk scripting language to automate most of the required steps. The procedure is separated into three main parts. The first consists of preliminary checks that verify that the hardware is set correctly and that systems are ready to be activated. The second part turns on the main interlocked systems including high power magnets and RF. The final step turns on the beam and verifies that the beam quality is satisfactory by measuring the transmission, orbit, bunch length, transverse emittance and match, energy spread, and dispersion. Minor corrections for phasing are also performed in the program. In order to identify inefficiencies in the startup, each step is timed and parameter changes are logged so that system drifts can be tracked. This paper describes the software implementation, the logic to achieve a successful startup, and efficiency results.

  12. Survey and Alignment of the 100MeV Linear Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Park, Bumsik; Kwon, Hyeokjung; Jang, Jiho; Kim, Hansung; Kim, Daeil; Cho, Yongsub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The 100MeV linear accelerator was installed and under commissioning at the Gyeongju site. The 100MeV proton linac was developed by the KOMAC according to the survey work and the alignment process. 100MeV proton beam will be supplied to the users after the beam commissioning. KOMAC is developing a 100MeV high-duty-factor proton linac. Linac is composed with a 50keV proton injector, a 3MeV RFQ, DTL tanks and a beam dump. In this paper, the survey and alignment scheme are described. To install the accelerator, the align network was built and the survey work was accomplished. On the basis of the survey result, all of the accelerator components were installed in the tunnel with two laser trackers.

  13. Study on strontium isotope abundance-ratio measurements by using a 13-MeV proton beam

    Science.gov (United States)

    Jeong, Cheol-Ki; Jang, Han; Lee, Goung-Jin

    2016-09-01

    The Rb-Sr dating method is used in dating Paleozoic and Precambrian rocks. This method measures the 87Rb and the 87Sr concentrations by using thermal ionization mass spectrometry (TIMS) [J. Hefne et al., Inter. J. Phys. Sci. 3(1), 28 (2008)]. In addition, it calculates the initial 87Sr/86Sr ratio to increase the reliability of Rb-Sr dating. In this study, the 87Sr/86Sr ratio was measured by using a 13-MeV proton accelerator. Proton kinetic energies are in the range of tens of megaelectronvolts, and protons have large absorption cross-sections for ( p, n) reactions with most substances. After absorbing a proton with such a high kinetic energy, an element is converted into a nuclide with its atomic number increased by one via nuclear transmutation. These nuclides usually have short half-lives and return to the original state through radioactive decay. When a strontium sample is irradiated with protons, nuclear transmutation occurs; thus, the strontium isotope present in the sample changes to a yttrium isotope, which is an activated radioisotope. Based on this, the 87Sr/86Sr ratio was calculated by analyzing the gamma-rays emitted by each yttrium isotope. The KIRAMS-13 cyclotron at the Cyclotron Center of Chosun University, where 13-MeV protons can be extracted, was utilized in our experiment. The 87Sr/86Sr isotope ratio was computed for samples irradiated with these protons, and the result was similar to the isotope ratio for the Standard Reference Material, i.e., 98.2 ± 3.4%. As part of the analysis, proton activation analyses were performed using 13-MeV protons, and the experimental results of this research suggest a possible approach for measuring the strontium-isotope abundance ratio of samples.

  14. Whole cell structural imaging at 20 nanometre resolutions using MeV ions

    Science.gov (United States)

    Watt, F.; Chen, X.; Chen, C.-B.; Udalagama, CNB; van Kan, J. A.; Bettiol, A. A.

    2013-07-01

    MeV proton and alpha (helium ion) particle beams can now be focused to 20 nm spot sizes, and ion/matter simulations using the DEEP computer code show that these resolutions are maintained through the top micrometre or so of organic material. In addition, the energy deposition profiles of the transmitted ions are laterally constrained to a few nanometers from the initial ion path. This paves the way for high resolution structural imaging of relatively thick biological material, e.g. biological cells. Examples are shown of high resolution structural imaging of whole biological cells (MRC5) using on-axis scanning transmission ion microscopy (STIM). Nanoparticles have the ability to cross the cell membrane, and may therefore prove useful as drug delivery probes. We show that the combination of on-axis STIM for imaging the cell interior, and off-axis STIM for imaging gold nanoparticles with enhanced contrast within the cell, represents a powerful set of ion beam techniques for tracking gold nanoparticles in biological cells. Whole cell imaging at high spatial resolutions represents a new area for nuclear microprobes.

  15. Consistency of neutron cross-section data, S /SUB N/ calculations, and measured tritium production for a 14-MeV neutron-driven sphere of natural lithium deuteride

    Energy Technology Data Exchange (ETDEWEB)

    Reupke, W.A.; Davidson, J.N.; Muir, D.W.

    1982-12-01

    The authors present algorithms, describe a computer program, and gives a computational procedure for the statistical consistency analysis of neutron cross-section data, S /SUB N/ calculations, and measured tritium production in 14-MeV neutron-driven integral assemblies. Algorithms presented include a reduced matrix manipulation technique suitable for manygroup, 14-MeV neutron transport calculations. The computer program incorporates these algorithms and is expanded and improved to facilitate analysis of such integral experiments. Details of the computational procedure are given for a natural lithium deuteride experiment performed at the Los Alamos National Laboratory. Results are explained in terms of calculated cross-section sensitivities and uncertainty estimates. They include a downward adjustment of the /sup 7/Li(n,xt) 14-MeV cross section from 328 + or - 22 to 284 + or - 24 mb, which is supported by the trend of recent differential and integral measurements. It is concluded that with appropriate refinements, the techniques of consistency analysis can be usefully applied to the analysis of 14-MeV neutron-driven tritium production integral experiments.

  16. Two body photodisintegration of the deuteron from 100 to 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, R.; Annand, J.R.M.; Anthony, I. [Glasgow Univ. (United Kingdom). Dept. of Physics and Astronomy; Ahrens, J.; Beck, R. [Mainz Univ. (Germany). Inst. fuer Kernphysik; Braghieri, A.; Pedroni, P. [Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Altieri, S. [Istituto Nazionale di Fisica Nucleare, Pavia (Italy)]|[Pavia Univ. (Italy). Ist. di Fisica Nucleare; Audit, G.; D`Hose, N. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee] [and others

    1996-01-01

    The total and the differential cross sections for the D({gamma},p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 deg-160 deg in 10 deg intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and the results compared with some recent theoretical calculations. (author). Submitted to Nuclear Physics, B (NL); 23 refs.

  17. On the Origin of the MeV $\\gamma$-Ray Background

    CERN Document Server

    Stecker, F W; Done, C

    1999-01-01

    In this paper, we suggest a new hypothesis for explaining the spectrum of the extragalactic MeV gamma-ray background as observed by COMPTEL and SMM. We propose that both the flux level and spectrum can be accounted for as a superposition of non-thermal MeV tails in the spectra of Seyfert galaxies and other AGN. Although present detectors are not sensitive enough to obtain MeV data from individual extragalactic sources, indirect evidence in support of our hypothesis is found in OSSE and COMPTEL observations of the galactic black hole candidate Cygnus X-1.

  18. Pion absorption processes. [32 to 74 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Doss, K G.R.

    1980-04-01

    Proton and deuteron production from low-energy pion absorption in light nuclei leading to discrete and continuum states were measured. The LEP beam line at LAMPF was used with a stack of 8 intrinsic germanium crystals. The proton energy spectra are in general characterized by a broad bump at an energy approximately corresponding to ..pi../sup +/d ..-->.. pp reaction kinematics, suggestive of pion absorption on 2 nucleons. The energy-integrated cross-section for production of deuterons has an angular distribution similar to that for production of protons. The dependence of the total pion absorption cross-section on A is explained using a semi-classical model for pion transport in nuclei. The (..pi../sup +/,p) as well as (..pi../sup +/,d) reactions generally favor transitions involving larger angular momentum transfer to the residual nucleus when states of similar nuclear structure are considered. The low-energy excitation spectra from the (..pi../sup +/,p) reaction are similar to the spectra from (p,d) reaction on /sup 12/C and /sup 13/C. However, a calculation of the (..pi.. = ,p) cross-section using the measured (p,d) reaction with the formulation of Wilkin to relate the two reactions is in moderate disagreement with the measured (..pi../sup +/,p) cross-sections. The excitation spectra from the (..pi../sup +/,p) reaction indicte the importance of two-step processes for the reaction. The (..pi../sup +/,d) reaction leading to the ground state of -- residual nucleus has been seen for /sup 7/Li, /sup 12/C, and /sup 13/C targets. The measured cross section for the /sup 12/C(..pi../sup +/,d)/sup 10/C reaction to the 2/sup +/ state is much higher than that for the ground state. For the case of /sup 18/O, no counts were seen for excitation energy of < 10 MeV, at a sensitivity of approx. 100 nb/sr count. These features indicate a possible failure of the model of Betz and Kerman for the (..pi../sup +/,d) reaction.

  19. Comparison of bactericidal efficiency of 7.5 MeV X-rays, gamma-rays, and 10 MeV e-beams

    Science.gov (United States)

    Song, Beom-Seok; Lee, Yunjong; Moon, Byeong-Geum; Go, Seon-Min; Park, Jong-Heum; Kim, Jae-Kyung; Jung, Koo; Kim, Dong-Ho; Ryu, Sang-Ryeol

    2016-08-01

    This study was performed to verify the feasibility of 7.5 MeV X-rays for food pasteurization through a comparison of the bactericidal efficiency with those of other sources for selected bacterial pathogens. No significant differences were observed between the overall bactericidal efficiency for beef-inoculated pathogens based on the uncertainty of the absorbed dose and variations in bacterial counts. This result supported that all three irradiation sources were effective for inactivation of food-borne bacteria and that 7.5 MeV X-rays may be used for food pasteurization.

  20. An improved time of flight gamma-ray telescope to monitor diffuse gamma-ray in the energy range 5 MeV - 50 MeV

    Science.gov (United States)

    Dacostafereiraneri, A.; Bui-Van, A.; Lavigne, J. M.; Sabaud, C.; Vedrenne, G.; Agrinier, B.; Gouiffes, C.

    1985-01-01

    A time of flight measuring device is the basic triggering system of most of medium and high energy gamma-ray telescopes. A simple gamma-ray telescope has been built in order to check in flight conditions the functioning of an advanced time of flight system. The technical ratings of the system are described. This telescope has been flown twice with stratospheric balloons, its axis being oriented at various Zenital directions. Flight results are presented for diffuse gamma-rays, atmospheric secondaries, and various causes of noise in the 5 MeV-50 MeV energy range.

  1. Design study for a 500 MeV proton synchrotron with CSNS linac as an injector

    Science.gov (United States)

    Huang, Liang-Sheng; Ji, Hong-Fei; Wang, Sheng

    2016-09-01

    Using the China Spallation Neutron Source (CSNS) linac as the injector, a 500 MeV proton synchrotron is proposed for multidisciplinary applications, such as biology, material science and proton therapy. The synchrotron will deliver proton beam with energy from 80 MeV to 500 MeV. A compact lattice design has been worked out, and all the important beam dynamics issues have been investigated. The 80 MeV H- beam is stripped and injected into the synchrotron by using multi-turn injection. In order to continuously extraction the proton with small beam loss, an achromatic structure is proposed and a slow extraction method with RF knock-out is adopted and optimized.

  2. Induced photonuclear interaction by Rhodotron-TT200 10 MeV electron beam

    Indian Academy of Sciences (India)

    Farshid Tabbakh; Mojtaba Mostajab Aldaavati; Mahdieh Hoseyni; Khadijeh Rezaee Ebrahim Saraee

    2012-02-01

    In this paper the photonuclear interaction induced by 10 MeV electron beam generating high-intensity neutrons is studied. Since the results depend on the target material, the calculations are performed for Pb, Ta and W targets which have high , in a simple geometry. MCNPX code has been used to simulate the whole process. Also, the results of photon generation has been compared with the experimental results to evaluate the reliability of the calculation. The results show that the obtained neutron flux can reach up to 1012 n/cm2 /s with average energies of 0.9 MeV, 0.4 MeV and 0.9 MeV for these three elements respectively with the maximum heat deposited as 3000 W/c3,4500 W/c3 and 6000 W/c3.

  3. Beam diagnostics measurements at 3 MeV of the LINAC4 H- beam at CERN

    CERN Document Server

    Zocca, F; Duraffourg, M; Focker, G J; Gerard, D; Kolad, B; Lenardon, F; Ludwig, M; Raich, U; Roncarolo, F; Sordet, M; Tan, J; Tassan-Viol, J; Vuitton, C; Feshenko, A

    2014-01-01

    As part of the CERN LHC injector chain upgrade, LINAC4 [1, 2] will accelerate H- ions to 160 MeV, replacing the old 50 MeV proton linac. The ion source, the Low Energy Beam Transfer (LEBT) line, the 3 MeV Radio Frequency Quadrupole and the Medium Energy Beam Transfer (MEBT) line hosting a chopper, have been commissioned in the LINAC4 tunnel. Diagnostic devices are installed in the LEBT and MEBT line and in a movable diagnostics test bench which is temporarily added to the MEBT exit. The paper gives an overview of all the instruments used, including beam current transformers, beam position monitors, wire scanners and wire grids for transverse profile measurements, a longitudinal bunch shape monitor and a slit-and-grid emittance meter. The instrumentation performance is discussed and the measurement results that allowed characterizing the 3 MeV beam in the LINAC4 tunnel are summarized.

  4. Coulomb dissociation of {sup 8}B at 254 A MeV

    Energy Technology Data Exchange (ETDEWEB)

    Suemmerer, K.; Boue, F.; Baumann, T.; Geissel, H.; Hellstroem, M.; Koczon, P.; Schwab, E.; Schwab, W.; Senger, P.; Surowiecz, A. [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany); Iwasa, N.; Ozawa, A. [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany)]|[RIKEN Institute of Physical and Chemical Research, Saitama (Japan); Surowka, G. [Gesellschaft fuer Schwerionenforschung (GSI), Darmstadt (Germany)]|[Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Blank, B.; Czajkowski, S.; Marchand, C.; Pravikoff, M.S. [Centre d`Etudes Nucleaires de Bordeaux-Gradignan, 33 (France); Foerster, A.; Lauer, F.; Oeschler, H.; Speer, J.; Sturm, C.; Uhlig, F.; Wagner, A. [Technische Univ. Darmstadt (Germany); Gai, M. [Connecticut Univ., Storrs, CT (United States). Dept. of Physics; Grosse, E. [Inst. fuer Kern- und Hadronenphysik, Forschungszentrum Rossendorf, Dresden (Germany); Kohlmeyer, B. [Philipps Univ., Marburg (Germany). Fachbereich Physik; Kulessa, R.; Walus, W. [Jagiellonian Univ., Krakow (Poland). Inst. of Physics; Motobayashi, T. [Rikkyo Univ., Tokyo (Japan). Dept. of Physics; Teranishi, T. [RIKEN Institute of Physical and Chemical Research, Saitama (Japan)

    1998-06-01

    As an alternative method for determining the astrophysical S-factor for the {sup 7}Be(p,{gamma}){sup 8}B reaction we have measured the Coulomb dissociation of {sup 8}B at 254 A MeV. From our preliminary results, we obtain good agreement with both the accepted direct-reaction measurements and the low-energy Coulomb dissociation study of Iwasa et al. performed at about 50 A MeV. (orig.)

  5. Measurement of Prompt Fission Neutron Spectrum of 238U at 2.8 MeV

    Institute of Scientific and Technical Information of China (English)

    HUANG; Han-xiong; RUAN; Xi-chao; REN; Jie; LI; Guang-wu; LUAN; Guang-yuan

    2015-01-01

    The prompt fission neutron spectrum(PFNS,Fig.1)of 238U was measured at 2.8MeV incident neutron energy by using the Cockcroft&Walton accelerator in China Institute of Atomic Energy(CIAE).The effect-to-background ratio was improved by increasing the amount of sample mass and adding an appropriate shielding.The final uncertainty of neutron energy spectrum is less than 20%below 10MeV region at an bin size

  6. (n,Xn) measurements at 100 MeV. Recent developments and first results

    Energy Technology Data Exchange (ETDEWEB)

    Blideanu, V. [Lab. de Physique Corpusculaire, Caen (France); Blomgren, J.; Eudes, P.; Fontbonne, J.M.; Foucher, Y.; Guertin, A.; Hadad, F.; Hay, L.; Hildebrand, A.; Iltis, G.; Le Brun, C.; Lecolley, F.R.; Lecolley, J.F.; Lefort, T.; Louvel, M.; Mermod, P.; Marie, N.; Olsson, N.; Pomp, S.; Osterlund, M.; Prokoviev, A.V.

    2003-07-01

    In the framework of the HINDAS project, we have studied the feasibility of (n,Xn) measurements at intermediate energy (20-200 MeV). To achieve this goal, we have developed a new set-up and performed several experiments using the monoenergetic neutron beam facility at the Svedberg laboratory (Sweden). The performance of this set-up is illustrated by first results obtained in 100 MeV neutron-induced reactions on a lead target. (orig.)

  7. High energy resolution characteristics on 14MeV neutron spectrometer for fusion experimental reactor

    Energy Technology Data Exchange (ETDEWEB)

    Iguchi, Tetsuo [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.; Takada, Eiji; Nakazawa, Masaharu

    1996-10-01

    A 14MeV neutron spectrometer suitable for an ITER-like fusion experimental reactor is now under development on the basis of a recoil proton counter telescope principle in oblique scattering geometry. To verify its high energy resolution characteristics, preliminary experiments are made for a prototypical detector system. The comparison results show reasonably good agreement and demonstrate the possibility of energy resolution of 2.5% in full width at half maximum for 14MeV neutron spectrometry. (author)

  8. The cosmic monster quest: hunting MeV blazars with AMEGO

    Science.gov (United States)

    Buson, Sara; Ajello, Marco; Sharan Paliya, Vaidehi; Hartmann, Dieter; Venters, Tonia M.

    2017-08-01

    The All-Sky Medium Energy Gamma-ray Observatory (AMEGO) will explore the energy regime from 200 keV and 10 GeV with unprecedented sensitivity. Its wide field of view will allow us to observe the entire sky every three hours, making AMEGO a prime mission to study the long-term and short-term behavior of Active Galactic Nuclei (AGN) in the MeV band. This relatively unexplored energy range is particularly important since it enables us to investigate the emission mechanisms and environments of the MeV blazars, i.e. AGN whose peak power output lies in the MeV range. These distant MeV blazars host monster black holes, i.e., >1 billion solar mass, and are some of the most luminous and most distant gamma-ray AGN. Beside helping us in studying the evolution of supermassive black holes in the early Universe, MeV blazars play a key role in the context of extragalactic gamma ray background studies, especially in the challenging MeV regime.

  9. Measurement of the Am241(n,2n) reaction cross section from 7.6 MeV to 14.5 MeV

    Science.gov (United States)

    Tonchev, A. P.; Angell, C. T.; Boswell, M.; Crowell, A. S.; Fallin, B.; Hammond, S.; Howell, C. R.; Hutcheson, A.; Karwowski, H. J.; Kelley, J. H.; Pedroni, R. S.; Tornow, W.; Becker, J. A.; Dashdorj, D.; Kenneally, J.; Macri, R. A.; Stoyer, M. A.; Wu, C. Y.; Bond, E.; Chadwick, M. B.; Fitzpatrick, J.; Kawano, T.; Rundberg, R. S.; Slemmons, A.; Vieira, D. J.; Wilhelmy, J. B.

    2008-05-01

    The (n,2n) cross section of the radioactive isotope Am241 (T1/2=432.6 y) has been measured in the incident neutron energy range from 7.6 to 14.5 MeV in steps of a few MeV using the activation technique. Monoenergetic neutron beams were produced via the H2(d,n)He3 reaction by bombarding a pressurized deuterium gas cell with an energetic deuteron beam at the TUNL 10-MV Van de Graaff accelerator facility. The induced γ-ray activity of Am240 was measured with high-resolution HPGe detectors. The cross section was determined relative to Al, Ni, and Au neutron activation monitor foils, measured in the same geometry. Good agreement is obtained with previous measurements at around 9 and 14 MeV, whereas for a large discrepancy is observed when our data are compared to those reported by Perdikakis near 11 MeV. Very good agreement is found with the END-B/VII evaluation, whereas the JENDL-3.3 evaluation is in fair agreement with our data.

  10. Measurement of (n,Xn) reaction cross sections at 96 MeV; Measure des sections efficaces (n,Xn) a 96 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Sagrado Garcia, Melle Inmaculada C. [Ecole Doctorale: SINEM, U.F.R. de Sciences, Universite de Caen/Basse-Normandie, Esplanade Paix14000 Caen (France)

    2006-10-15

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n,Xn) reactions in this energy range. Neutron double differential cross section measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL Laboratory in Uppsala, Sweden. The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 angle - 98 angle). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100) MeV. The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparison between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its treatment of nucleon-nucleon reactions. (author)

  11. Complete identification of states in 208Pb below Ex=6.2 MeV

    Science.gov (United States)

    Heusler, A.; Jolos, R. V.; Faestermann, T.; Hertenberger, R.; Wirth, H.-F.; von Brentano, P.

    2016-05-01

    The Q3D magnetic spectrograph at the Maier-Leibnitz-Laboratorium of the Ludwig-Maximilians-Universität München and the Technische Universität München (Garching, Germany), was used to study the 208Pb(p ,p' ) , 206,207,208Pb (d,p), and 208Pb(d ,d' ) reactions. One hundred fifty-one states at Ex<6.20 MeV in 208Pb are identified and spin and parity assigned. Four states are newly identified and new spins and/or parities are assigned to 25 states. Tentative spin assignments are done to five states at 5.90 MeV . Nearly 50 levels below Ex=6.20 MeV listed by the Nuclear Data Sheets as of 2007 are recognized to be nonexistent or doubly placed. The schematic shell model describing one-particle-one-hole configurations without residual interaction is extended by including two-particle-two-hole configurations. The number of configurations thus predicted at Ex<6.20 MeV nearly agrees with the number of states identified. Several states with dominant two-particle-two-hole configurations are identified. New isobaric analog resonances in 209Bi with two-particle-one-hole structure are discovered at Eres=17.6 MeV . The excitation energies of 70 states with unnatural parity at Ex<6.20 MeV are found to agree within about 200 keV with one-particle-one-hole configurations predicted by the extended schematic shell model. In contrast, the excitation energies of about 20 natural parity states are more than 0.5 MeV lower than predicted, demonstrating the residual interaction among the configurations to be much larger for natural parity than for unnatural parity.

  12. Neutron-induced fission cross sections of 242Pu from 0.3 MeV to 3 MeV

    Science.gov (United States)

    Salvador-Castiñeira, P.; Bryś, T.; Eykens, R.; Hambsch, F.-J.; Göök, A.; Moens, A.; Oberstedt, S.; Sibbens, G.; Vanleeuw, D.; Vidali, M.; Pretel, C.

    2015-10-01

    The majority of the next generation of nuclear power plants (GEN-IV) will work in the fast-neutron-energy region, as opposed to present day thermal reactors. This leads to new and more accurate nuclear-data needs for some minor actinides and structural materials. Following those upcoming demands, the Organisation for Economic Cooperation and Development Nuclear Energy Agency performed a sensitivity study. Based on the latter, an improvement in accuracy from the present 20% to 5% is required for the 242Pu(n ,f ) cross section. Within the same project both the 240Pu(n ,f ) cross section and the 242Pu(n ,f ) cross section were measured at the Van de Graaff accelerator of the Joint Research Centre at the Institute for Reference Materials and Measurements, where quasimonoenergetic neutrons were produced in an energy range from 0.3 MeV up to 3 MeV. A twin Frisch-grid ionization chamber has been used in a back-to-back configuration as fission-fragment detector. The 242Pu(n ,f ) cross section has been normalized to three different isotopes: 237Np(n ,f ) , 235U(n ,f ) , and 238U(n ,f ) . A comprehensive study of the corrections applied to the data and the uncertainties associated is given. The results obtained are in agreement with previous experimental data at the threshold region up to 0.8 MeV. The resonance-like structure at 0.8 to 1.1 MeV, visible in the evaluations and in most previous experimental values, was not reproduced with the same intensity in this experiment. For neutron energies higher than 1.1 MeV, the results of this experiment are slightly lower than the Evaluated Nuclear Data File/B-VII.1 evaluation but in agreement with the experiment of Tovesson et al. (2009) as well as Staples and Morley (1998). Finally, for energies above 1.5 MeV, the results show consistency with the present evaluations.

  13. Shielding calculations for industrial 5/7.5MeV electron accelerators using the MCNP Monte Carlo Code

    Science.gov (United States)

    Peri, Eyal; Orion, Itzhak

    2017-09-01

    High energy X-rays from accelerators are used to irradiate food ingredients to prevent growth and development of unwanted biological organisms in food, and by that extend the shelf life of the products. The production of X-rays is done by accelerating 5 MeV electrons and bombarding them into a heavy target (high Z). Since 2004, the FDA has approved using 7.5 MeV energy, providing higher production rates with lower treatments costs. In this study we calculated all the essential data needed for a straightforward concrete shielding design of typical food accelerator rooms. The following evaluation is done using the MCNP Monte Carlo code system: (1) Angular dependence (0-180°) of photon dose rate for 5 MeV and 7.5 MeV electron beams bombarding iron, aluminum, gold, tantalum, and tungsten targets. (2) Angular dependence (0-180°) spectral distribution simulations of bremsstrahlung for gold, tantalum, and tungsten bombarded by 5 MeV and 7.5 MeV electron beams. (3) Concrete attenuation calculations in several photon emission angles for the 5 MeV and 7.5 MeV electron beams bombarding a tantalum target. Based on the simulation, we calculated the expected increase in dose rate for facilities intending to increase the energy from 5 MeV to 7.5 MeV, and the concrete width needed to be added in order to keep the existing dose rate unchanged.

  14. Highly Stripped Ion Sources for MeV Ion Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hershcovitch, Ady

    2009-06-30

    Original technical objectives of CRADA number PVI C-03-09 between BNL and Poole Ventura, Inc. (PVI) were to develop an intense, high charge state, ion source for MeV ion implanters. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with rf accelerators. Usually, a MV LINAC is used for acceleration of a few rnA. It is desirable to have instead an intense, high charge state ion source on a relatively low energy platform (de acceleration) to generate high-energy ion beams for implantation. This de acceleration of ions will be far more efficient (in energy utilization). The resultant implanter will be smaller in size. It will generate higher quality ion beams (with lower emittance) for fabrication of superior semiconductor products. In addition to energy and cost savings, the implanter will operate at a lower level of health risks associated with ion implantation. An additional aim of the project was to producing a product that can lead to long­ term job creation in Russia and/or in the US. R&D was conducted in two Russian Centers (one in Tomsk and Seversk, the other in Moscow) under the guidance ofPVI personnel and the BNL PI. Multiple approaches were pursued, developed, and tested at various locations with the best candidate for commercialization delivered and tested at on an implanter at the PVI client Axcelis. Technical developments were exciting: record output currents of high charge state phosphorus and antimony were achieved; a Calutron-Bemas ion source with a 70% output of boron ion current (compared to 25% in present state-of-the-art). Record steady state output currents of higher charge state phosphorous and antimony and P ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb {sup 4 +}, Sb{sup 5+}, and Sb{sup 6+} respectively. Ultimate commercialization goals did not succeed (even though a number of the products like high

  15. Damage kinetics in MeV gold ion - Irradiated crystalline quartz

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, S.M.M. E-mail: ramos@dpm.univ-lyon1.fr; Clerc, C.; Canut, B.; Chaumont, J.; Toulemonde, M.; Bernas, H

    2000-05-02

    Damage creation in crystalline {alpha}-quartz under gold irradiation was studied at 1.0 and 5.5 MeV using the ARAMIS accelerator at CSNSM (Orsay). Although at these energies the total stopping powers are nearly equal (respectively, 4.20 and 4.46 keV nm{sup -1}), the electronic stopping power is only 1.23 keV nm{sup -1} (25% of the total) at 1 MeV while it reaches 2.75 keV nm{sup -1} (62% of the total) at 5.5 MeV. The electronic stopping power threshold for damage creation in {alpha}-quartz is about 1.8 keV/nm . The experiment thus allows us to follow the damage production kinetics due to nuclear collisions (at 1 MeV) versus electronic collisions (at 5.5 MeV). The damage was determined by channeling Rutherford backscattering (RBS-C) using the 2 MV Van de Graaff at DPM (Villeurbanne). Single ion impacts create damage when electronic stopping dominates, while several impacts are necessary to achieve complete damage when nuclear stopping dominates. Differences in damage efficiencies will be discussed.

  16. Elastic Neutron Scattering at 96 MeV from {sup 12}C and {sup 208}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Klug, J.; Blomgren, J.; Atac, A. [and others

    2003-04-01

    A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20-180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from {sup 12}C and {sup 208}Pb has been studied at 96 MeV in the 10-70 deg interval. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated uncertainty, 3 %, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic nuclear theory.

  17. Modification of semiconductor or metal nanoparticle lattices in amorphous alumina by MeV heavy ions

    Science.gov (United States)

    Bogdanović Radović, I.; Buljan, M.; Karlušić, M.; Jerčinović, M.; Dražič, G.; Bernstorff, S.; Boettger, R.

    2016-09-01

    In the present work we investigate effects of MeV heavy ions (from 0.4 MeV Xe to 15 MeV Si) on regularly ordered nanoparticle (NP) lattices embedded in amorphous alumina matrix. These nanostructures were produced by self-assembling growth using magnetron-sputtering deposition. From grazing incidence small-angle x-ray scattering measurements we have found that the used MeV heavy ions do not change the NP sizes, shapes or distances among them. However, ions cause a tilt of the entire NP lattice in the direction parallel to the surface. The tilt angle depends on the incident ion energy, type and the applied fluence and a nearly linear increase of the tilt angle with the ion fluence and irradiation angle was found. This way, MeV heavy ion irradiation can be used to design custom-made NP lattices. In addition, grazing incidence small-angle x-ray scattering can be effectively used as a method for the determination of material redistribution/shift caused by the ion hammering effect. For the first time, the deformation yield in amorphous alumina was determined for irradiation performed at the room temperature.

  18. Experimental and Calculated Effectiveness of a Radiochromic Dye Film to Stopping 21 MeV 7Li- and 64 MeV 16O Ions

    DEFF Research Database (Denmark)

    Olsen, Kjeld J; Hansen, Johnny

    1984-01-01

    particles developed by Katz et al. The experiment was designed to test calculations particularly in the Bragg-peak region of the slowing down particles where significant deviation between theory and experiment was found. Fitting of the characteristic D37 dose and the size of the radiation sensitive element......Relative radiation effectiveness, RE, of 21 MeV 7Li and 64 MeV 16O ions being completely stopped in a tissue equivalent film dose meter has been measured as a function of penetration depth and energy, and the results have been compared with calculations based on a δ-ray theory for heavy charged...... in the detector, which are important parameters in the theoretical model, does not improve the overall correlation between theory and experiment. It is concluded that disagreement between theoretical and experimental RE-values below 1.5 MeV/amu is partly due to lack of equivalence between the δ-ray spectrum...

  19. Independent isotopic yields in 25 MeV and 50 MeV proton-induced fission of {sup nat}U

    Energy Technology Data Exchange (ETDEWEB)

    Penttilae, H.; Gorelov, D.; Elomaa, V.V.; Eronen, T.; Hager, U.; Hakala, J.; Jokinen, A.; Kankainen, A.; Karvonen, P.; Moore, I.D.; Parkkonen, J.; Pohjalainen, I.; Rahaman, S.; Rinta-Antila, S.; Rissanen, J.; Saastamoinen, A.; Simutkin, V.; Sonoda, T.; Weber, C.; Voss, A.; Aeystoe, J. [Department of Physics, University of Jyvaskylae (Finland); Peraejaervi, K. [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland); Rubchenya, V.A. [Department of Physics, University of Jyvaskylae (Finland); V.G. Khlopin Radium Institute, St. Petersburg (Russian Federation)

    2016-04-15

    Independent isotopic yields for elements from Zn to La in the 25 MeV proton-induced fission of {sup nat}U were determined with the JYFLTRAP facility. In addition, isotopic yields for Zn, Ga, Rb, Sr, Zr, Pd and Xe in the 50 MeV proton-induced fission of {sup nat}U were measured. The deduced isotopic yield distributions are compared with a Rubchenya model, the GEF model with universal parameters and the semi-empirical Wahl model. Of these, the Rubchenya model gives the best overall agreement with the obtained data. Combining the isotopic yield data with mass yield data to obtain the absolute independent yields was attempted. The result depends on the mass yield distribution. (orig.)

  20. Digital neutron/gamma discrimination with an organic scintillator at energies between 1 MeV and 100 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Comrie, A.C. [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Buffler, A., E-mail: andy.buffler@uct.ac.za [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Smit, F.D. [iThemba LABS, Somerset West 7129 (South Africa); Wörtche, H.J. [INCAS" 3, Dr. Nassaulaan 9. 9400 AT Assen (Netherlands)

    2015-02-01

    Three different digital implementations of pulse shape discrimination for pulses from an EJ301 liquid scintillator detector are presented, and illustrated with neutrons and gamma-rays produced by an Am–Be radioisotopic source, a D–T generator and beams produced by cyclotron-accelerated protons of energies 42, 62 and 100 MeV on a Li target. A critical comparison between the three methods is provided.

  1. Calculating Rayleigh scattering amplitudes from 100 eV to 10 MeV. [100 eV to 10 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Parker, J.C.; Reynaud, G.W.; Botto, D.J.; Pratt, R.H.

    1979-05-01

    An attempt is made to explain how to calculate the contribution to elastic photon-atom scattering due to Rayleigh scattering (the scattering off bound electrons) in the photon energy range 100 eV less than or equal to W less than or equal to 10 MeV. All intermediate calculations are described, including the calculation of the potential, bound state wave functions, matrix elements, and final cross sections. 12 references. (JFP)

  2. Absolute calibration of the [sup 16]O([alpha],[alpha])[sup 16]O elastic scattering resonance at 7. 30-7. 65 MeV and applications to oxygen depth profiling

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, F.J.D. (Accelerator Lab., McMaster Univ., Hamilton, ON (Canada)); Davies, J.A. (Accelerator Lab., McMaster Univ., Hamilton, ON (Canada)); Jackman, T.E. (Inst. for Microstructural Sciences, National Research Council, Ottawa, ON (Canada))

    1993-08-01

    The differential cross-section of the [sup 16]O([alpha],[alpha])[sup 16]O elastic scattering resonance at 7.30-7.65 MeV has been calibrated with an overall accuracy of 4% at 170 scattering angle (laboratory frame of reference) using anodized Ta[sub 2]O[sub 5] films of pre-calibrated thickness as standards. This extremely strong (about 170 times the Rutherford cross-section) and broad (about 300 keV wide) resonance varies slowly with energy in the range 7.34-7.64 MeV, has a maximum value of 837 mb/sr at 7.61 MeV, and falls off abruptly above 7.64 MeV and below 7.34 MeV. The angular dependence of the resonance was measured in the range 140-172 at incident energy 7.62 MeV and was found to increase monotonically toward 180 . This strong resonance allowed us to measure the oxygen content in the very heavy element target ThO[sub 2] pellets and in oxidized InP substrates with detection sensitivity in the atomic monolayer range. The large width of this resonance allowed oxygen depth profiling to several microns with depth resolution a few tens of nm. Measurements combined with RUMP computer simulations using TRIM stopping cross-sections and our measured values of the elastic resonance scattering cross-section have been used to depth profile SiO[sub 2] surface and buried layers in SIMOX structures. (orig.)

  3. Scalability of the LEU-Modified Cintichem Process: 3-MeV Van de Graaff and 35-MeV Electron Linear Accelerator Studies

    Energy Technology Data Exchange (ETDEWEB)

    Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Brossard, Tom [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Roussin, Ethan [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Jonah, Charles [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hafenrichter, Lohman [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Krebs, John [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-10-31

    Molybdenum-99, the mother of Tc-99m, can be produced from fission of U-235 in nuclear reactors and purified from fission products by the Cintichem process, later modified for low-enriched uranium (LEU) targets. The key step in this process is the precipitation of Mo with α-benzoin oxime (ABO). The stability of this complex to radiation has been examined. Molybdenum-ABO was irradiated with 3 MeV electrons produced by a Van de Graaff generator and 35 MeV electrons produced by a 50 MeV/25 kW electron linear accelerator. Dose equivalents of 1.7–31.2 kCi of Mo-99 were administered to freshly prepared Mo-ABO. Irradiated samples of Mo-ABO were processed according to the LEU Modified-Cintichem process. The Van de Graaff data indicated good radiation stability of the Mo-ABO complex up to ~15 kCi dose equivalents of Mo-99 and nearly complete destruction at doses >24 kCi Mo-99. The linear accelerator data indicate that even at 6.2 kCi of Mo-99 equivalence of dose, the sample lost ~20% of Mo-99. The 20% loss of Mo-99 at this low dose may be attributed to thermal decomposition of the product from the heat deposited in the sample during irradiation.

  4. 25 MeV Solar Proton Events in Cycle 24 and Previous Cycles

    Science.gov (United States)

    Richardson, I. G.; Cane, H. V.; von Rosenvinge, T. T.

    2014-12-01

    We summarize observations of nearly 1000 solar energetic particle events that include 25 MeV protons made by Goddard instruments on various spacecraft (IMPs IV, V, 7, 8, ISEE-3) and by other instruments on SOHO, since 1967, encompassing solar cycles 20 to 24. We also include recent observations of such events from the STEREO spacecraft. These extended observations place studies focusing on Cycles 23 and 24 in a broader context. For example, the time distribution of 25 MeV proton events varies from cycle to cycle such that each cycle is unique. In the current cycle, ~25 MeV proton events were absent during the preceding solar minimum, whereas earlier minima showed occasional, often reasonably intense events, and there have been, so far, fewer exceptionally intense events compared to Cycles 22 and 23, though Cycle 21 also apparently lacked such events.

  5. The photoresponse of stable N=82 nuclei below 10 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Volz, S. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany)]. E-mail: volz@ikp.tu-darmstadt.de; Tsoneva, N. [Institut fuer Theoretische Physik, Universitaet Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen (Germany); Institute for Nuclear Research and Nuclear Energy, 1784 Sofia (Bulgaria); Babilon, M. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Elvers, M. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Hasper, J. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Herzberg, R.-D. [Department of Physics, The University of Liverpool, Liverpool L69 7ZE (United Kingdom); Lenske, H. [Institut fuer Theoretische Physik, Universitaet Giessen, Heinrich-Buff-Ring 16, D-35392 Giessen (Germany); Lindenberg, K. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Savran, D. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Zilges, A. [Institut fuer Kernphysik, TU Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany)

    2006-11-27

    High resolution photon scattering experiments were performed at the 10 MeV bremsstrahlung facility of the electron accelerator S-DALINAC at TU Darmstadt to investigate the semi-magic N=82 nuclei {sup 138}Ba, {sup 140}Ce, {sup 142}Nd and {sup 144}Sm. Energies and absolute strengths of dipole transitions below 10 MeV were determined in a model independent way. A concentration of electric dipole excitations exhausting up to 1% of the isovector E1 energy weighted sum rule is observed in all four nuclei around 6.5 MeV. Calculations in the framework of the Quasiparticle-Phonon Model (QPM) reproduce the gross experimental features.

  6. A possible approach to 14MeV neutron moderation: A preliminary study case.

    Science.gov (United States)

    Flammini, D; Pilotti, R; Pietropaolo, A

    2017-07-01

    Deuterium-Tritium (D-T) interactions produce almost monochromatic neutrons with about 14MeV energy. These neutrons are used in benchmark experiments as well as for neutron cross sections assessment in fusion reactors technology. The possibility to moderate 14MeV neutrons for purposes beyond fusion is worth to be studied in relation to projects of intense D-T sources. In this preliminary study, carried out using the MCNP Monte Carlo code, the moderation of 14MeV neutrons is approached foreseeing the use of combination of metallic materials as pre-moderator and reflectors coupled to standard water moderators. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Study of calf thymus DNA irradiated in vitro with MeV fluorine ions

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A study of the fragments of DNA irradiated with MeV ions is important for the understanding of the DNA damage mechanism and the subsequent biological effects (induced by heavy ions). In this experiment, the products of calf thymus DNA (CT DNA) irradiated with MeV fluorine ions were analyzed using agarose gel electrophoresis,modified time-of-flight mass spectrometer (MALDI-TOF), and high-performance liquid chromatography (HPLC).The results showed that the molecular mass of the fragments were concentrated around 831 bp with agarose gel electrophoresis, there was no observable product in the range of 1,000- 30,000 (m/q) using MALDI-TOF, and small biomolecules were separated from the products. The results of this study indicated that the strand breaks of calf thymus DNA induced by MeV fluorine ions were nonrandom.

  8. Relativistic analysis of nuclear ground state densities at 135 to 200 MeV

    Indian Academy of Sciences (India)

    M A Suhail; N Neeloffer; Z A Khan

    2005-12-01

    A relativistic analysis of p + 40Ca elastic scattering with different nuclear ground state target densities at 135 to 200 MeV is presented in this paper. It is found that the IGO densities are more consistent in reproducing the data over the energy range considered here. The reproduction of spin-rotation-function data with the simultaneous fitting of differential cross-section and analyzing power, and the appearance of wine-bottle-bottom shaped Re eff() in the transition energy region, sensitively depends on the input nuclear ground state densities and are not solely the relativistic characteristic signatures. We also found that the wine-bottle-bottom shaped Re eff() is preferred by the spin observables in the transition energy region (i.e. 181 MeV to 200 MeV).

  9. 50 MeV Run of the IOTA / FAST Electron Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Edstrom Jr., D.; et al.

    2017-02-02

    The low-energy section of the photoinjector-based electron linear accelerator at the Fermilab Accelerator Science & Technology (FAST) facility was recently commissioned to an energy of 50 MeV. This linear accelerator relies primarily upon pulsed SRF acceleration and an optional bunch compressor to produce a stable beam within a large operational regime in terms of bunch charge, total average charge, bunch length, and beam energy. Various instrumentation was used to characterize fundamental properties of the electron beam including the intensity, stability, emittance, and bunch length. While much of this instrumentation was commissioned in a 20 MeV running period prior, some (including a new Martin- Puplett interferometer) was in development or pending installation at that time. All instrumentation has since been recommissioned over the wide operational range of beam energies up to 50 MeV, intensities up to 4 nC/pulse, and bunch structures from ~1 ps to more than 50 ps in length.

  10. Neutron-proton analyzing power measurements from 375 to 775 MeV

    Science.gov (United States)

    Newsom, C. R.; Hollas, C. L.; Ransome, R. D.; Riley, P. J.; Bonner, B. E.; Boissevain, J. G. J.; Jarmer, J. J.; McNaughton, M. W.; Simmons, J. E.; Bhatia, T. S.; Glass, G.; Hiebert, J. C.; Northcliffe, L. C.; Tippens, W. B.

    1989-03-01

    As part of an experimental study of the nucleon-nucleon interaction at medium energy, the free neutron-proton analyzing power An(θ*n,Tn) has been measured at nine incident neutron energies in the range 375<=Tn<=775 MeV and for neutron c.m. angles in the range 57°<=θ*n<=159°. Unpolarized neutrons with a broad continuum of energies, produced by interaction of an 800 MeV proton beam with a beryllium target, were scattered from a polarized proton target. At each angle, for the whole energy region, the scattered neutron and conjugate recoil proton were detected in coincidence. A previously unseen minimum is observed in the energy dependence of An(θ*~100°) near 625 MeV.

  11. Nuclear spin response of sup 40 Ca to 800 MeV polarized protons

    Energy Technology Data Exchange (ETDEWEB)

    Bimbot, L.; Fergerson, R.W.; Glashausser, C.; Jones, K.W.; Baker, F.T.; Beatty, D.; Cupps, V.; Green, A.; Nanda, S. (Institut de Physique Nucleaire, F-91406 Orsay, France (FR) Rutgers University, New Brunswick, NJ 08903 Los Alamos National Laboratory, Los Alamos, New Mexico 87545 University of Georgia, Athens, Georgia 30602 Continuous Electron Beam Accelerator Facility, Newport News, Virginia 23606)

    1990-12-01

    Doubly differential cross sections and spin-flip probabilities have been measured for 800-MeV proton scattering on {sup 40}Ca at 3.2{degree}, 4{degree}, 5{degree}, and 7{degree} in the laboratory, for excitation energies up to 45 MeV. The features of these observables in the continuum are discussed. The data indicate that nuclear spin excitations are enhanced at high excitation energy for angles corresponding to momentum transfers around 100 MeV/{ital c}, as previously observed for incident energies around 300 MeV. The relative nuclear spin response derived from these data is roughly independent of energy. This suggests that the dominance of spin-transfer excitation at high excitation energies for momentum transfers around 100 MeV/{ital c} is an intrinsic feature of the nuclear structure of {sup 40}Ca.

  12. A direct electron detector for time-resolved MeV electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Vecchione, T.; Denes, P.; Jobe, R. K.; Johnson, I. J.; Joseph, J. M.; Li, R. K.; Perazzo, A.; Shen, X.; Wang, X. J.; Weathersby, S. P.; Yang, J.; Zhang, D.

    2017-03-01

    The introduction of direct electron detectors enabled the structural biology revolution of cryogenic electron microscopy. Direct electron detectors are now expected to have a similarly dramatic impact on time-resolved MeV electron microscopy, particularly by enabling both spatial and temporal jitter correction. Here we report on the commissioning of a direct electron detector for time-resolved MeV electron microscopy. The direct electron detector demonstrated MeV single electron sensitivity and is capable of recording megapixel images at 180 Hz. The detector has a 15-bit dynamic range, better than 30-μmμm spatial resolution and less than 20 analogue-to-digital converter count RMS pixel noise. The unique capabilities of the direct electron detector and the data analysis required to take advantage of these capabilities are presented. The technical challenges associated with generating and processing large amounts of data are also discussed.

  13. Depth profiling of fingerprint and ink signals by SIMS and MeV SIMS

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, M.J., E-mail: m.bailey@surrey.ac.u [University of Surrey Ion Beam Centre, Surrey GU2 7XH (United Kingdom); Jones, B.N. [University of Surrey Ion Beam Centre, Surrey GU2 7XH (United Kingdom); Hinder, S.; Watts, J. [Surface Analysis Laboratory, University of Surrey, GU2 7XH (United Kingdom); Bleay, S. [Home Office Scientific Development Branch, St. Albans (United Kingdom); Webb, R.P. [University of Surrey Ion Beam Centre, Surrey GU2 7XH (United Kingdom)

    2010-06-15

    Police institutions currently have no analytical method of knowing whether a fingerprint was deposited before or after the document was written or printed. The suitability of using MeV secondary ion mass spectrometry (i.e. SIMS with an MeV ion beam) to determine the order in which a fingerprint and written text were deposited on paper was therefore investigated. A 10 MeV O{sup 4+} beam was used to generate secondary ions from the surface of the samples and to map the molecular fragments from doped fingerprints and inks on paper. The images obtained and the sputtering behaviour of the samples was found to be indicative of the sequence of ink and fingerprint deposits.

  14. Resonance frequency control for the KOMAC 100-MeV drift tube linac

    Science.gov (United States)

    Kwon, Hyeok-Jung

    2015-02-01

    A 100-MeV proton accelerator has been developed, and the operation and beam service started at the Korea Multi-purpose Accelerator Complex (KOMAC) in July 2013. The accelerator consists of a 50-keV proton injector, a 3-MeV radio-frequency quadrupole (RFQ) and a 100-MeV drift tube linac (DTL). The resonance frequencies of the DTL tanks are controlled by using the resonance frequency control cooling system (RCCS), installed at every DTL tank. Until now, the RCCS has been operating in the constant temperature mode. If the system is to be stabilized better, the RCCS must be operated in the frequency control mode. For this purpose, studies, including the relation between the resonance frequency and RCCS operation temperature, were done under various conditions. In this paper, the preparations for the frequency control loop of the RCCS are described.

  15. Splitting Behaviour of Implanted MeV Au+ Ions in LiB3O5

    Institute of Scientific and Technical Information of China (English)

    WANG Ke-ming; SHI Bo-rong; Nelson Cue; LU Fei; WANG Feng-xiang; XIE Zhao-xia; SHEN Ding-yu; LIU Yao-gang

    2000-01-01

    The diffusion behaviour of 1.0 and 2.0 MeV Au+ implanted into LiB3O5 single crystal has been studied by the Rutherford backscattering of 2.1 MeV He ions. Annealing was performed at temperatures of 600, 700, and 800℃each for 30min. The results show that the diffusion behaviour is quite different in two cases. In LiB3O5, the depth distribution of the 1.0 Me V Au is nearly Gaussian and becomes bimodal after annealing at 800℃ for 30 min.But in the case of 2.0 MeV, the depth distribution of as implanted Au+ in LiBsO5 has splitting behaviour. After 800C for 30 min annealing, there is no obvious diffusion observed. The precise interpretation is needed.

  16. First commissioning experience with the LINAC4 3 MeV front-end at CERN

    CERN Document Server

    Lallement, J B; Bellodi, G; Comblin, J F; Dimov, V A; Granemann Souza, E; Lettry, J; Lombardi, A M; Midttun, O; Ovalle, E; Raich, U; Roncarolo, F; Rossi, C; Sanchez Alvarez, R; Scrivens, C A; Valerio-Lizarraga, C A; Vretenar, M; Yarmohammadi Satri, M

    2013-01-01

    Linac4 is a normal-conducting 160 MeV H- linear accelerator presently under construction at CERN. It will replace the present 50 MeV Linac2 as injector of the proton accelerator complex as part of a project to increase the LHC luminosity. The Linac front-end, composed of a 45 keV ion source, a Low Energy Beam Transport (LEBT), a 352.2 MHz Radio Frequency Quadrupole (RFQ) and a Medium Energy Beam Transport (MEBT) housing a beam chopper, have been commissioned at the 3 MeV test stand during the first half of 2013. The status of the installation and the results of the first commissioning stage are presented in this paper.

  17. Dispersive spherical optical model of neutron scattering from Al27 up to 250 MeV

    CERN Document Server

    Molina, A; Quesada, J M; Lozano, M

    2002-01-01

    A spherical optical model potential (OMP) containing a dispersive term is used to fit the available experimental database of angular distribution and total cross section data for n + Al27 covering the energy range 0.1- 250 MeV using relativistic kinematics and a relativistic extension of the Schroedinger equation. A dispersive OMP with parameters that show a smooth energy dependence and energy independent geometry are determined from fits to the entire data set. A very good overall agreement between experimental data and predictions is achieved up to 150 MeV. Inclusion of nonlocality effects in the absorptive volume potential allows to achieve an excellent agreement up to 250 MeV.

  18. Attenuation of 10 MeV electron beam energy to achieve low doses does not affect Salmonella spp. inactivation kinetics

    Science.gov (United States)

    Hieke, Anne-Sophie Charlotte; Pillai, Suresh D.

    2015-05-01

    The effect of attenuating the energy of a 10 MeV electron beam on Salmonella inactivation kinetics was investigated. No statistically significant differences were observed between the D10 values of either Salmonella 4,[5],12:i:- or a Salmonella cocktail (S. 4,[5],12:i:-, Salmonella Heidelberg, Salmonella Newport, Salmonella Typhimurium, Salmonella) when irradiated with either a non-attenuated 10 MeV eBeam or an attenuated 10 MeV eBeam (~2.9±0.22 MeV). The results show that attenuating the energy of a 10 MeV eBeam to achieve low doses does not affect the inactivation kinetics of Salmonella spp. when compared to direct 10 MeV eBeam irradiation.

  19. RF phase stability in the 100-MeV proton linac operation

    Science.gov (United States)

    Seol, Kyung-Tae

    2015-02-01

    The 100-MeV proton linac of the Korea multi-purpose accelerator complex (KOMAC) has been operated to provide a proton beam to users. The 100-MeV linac consists of a 3-MeV radio-frequency quadrupole accelerator (RFQ), four 20-MeV drift-tube linac (DTL) tanks, two medium-energy beam-transmitter (MEBT) tanks, and seven 100-MeV DTL tanks. The requirements of the field stability are within ±1% in RF amplitude and ±1 degree in RF phase. The RF phase stability is influenced by a RF reference line, RF transmission lines, and a RF control system. The RF reference signal is chosen to be a 300-MHz local oscillator (LO) signal, and a rigid copper coaxial line with temperature control was installed for an RF reference distribution. A phase stability of ±0.1 degrees was measured under a temperature change of ±0.1 °C. A digital feedback control system with a field-programmable gate-array (FPGA) module was adopted for a high RF stability. The RF phase was maintained within ±0.1 degrees with a dummy cavity and was within ±0.3 degrees at RFQ operation. In the case of the 20-MeV DTL tanks, one klystron drives 4 tanks, and the input phases of 4 tanks were designed to be in phase. The input phases of 4 tanks were fixed within ±1 degree by adjusting a phase shifter in each waveguide.

  20. Počeci igranja nogometa u Ðakovu

    OpenAIRE

    Bijelić, Borislav

    2008-01-01

    U članku se pokušava odgovoriti na pitanja kada se i u kakvim prilikama počeo igrati nogomet u Ðakovu. Na osnovi uvida u relativno skromnu građu, autor ističe kako se nogomet u Ðakovu organizirano igra već od 1908. godine te da je do izbijanja Drugoga svjetskog rata u gradu djelovalo nekoliko klubova. Prvi među njima koji je uspio opstati duže od godinu dana bio je Hrvatski športski klub “Orao”.

  1. Effect of 100MeV oxygen ion irradiation on silicon NPN power transistor

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, M. Vinay; Krishnakumar, K. S.; Dinesh, C. M.; Krishnaveni, S.; Ramani [Department of studies in Physics, University of Mysore, Mysore (India); Department of Physics, APS College, Bengaluru (India); Department of Physics, DCE, Govt. First Grade College, Mangalore (India); Department of studies in Physics, University of Mysore, Mysore (India); Department of Physics, Bangalore University, Bengaluru (India)

    2012-06-05

    The radiation response of npn Bipolar junction transistor (BJT) has been examined for 100 MeV O{sup 7+} ion. Key electrical properties like Gummel characteristics, dc current gain and capacitance-voltage of 100MeV O{sup 7+} ion irradiated transistor were studied before and after irradiation. The device was decapped and the electrical characterizations were performed at room temperature. Base current is observed to be more sensitive than collector current and gain appears to be degraded with ion fluence, also considerable degradation in C-V characteristics is observed and doping concentration is found to be increased along with the increase in ion fluence.

  2. Effect of 100MeV oxygen ion irradiation on silicon NPN power transistor

    Science.gov (United States)

    Kumar, M. Vinay; Krishnakumar, K. S.; Dinesh, C. M.; Krishnaveni, S.; Ramani

    2012-06-01

    The radiation response of npn Bipolar junction transistor (BJT) has been examined for 100 MeV O7+ ion. Key electrical properties like Gummel characteristics, dc current gain and capacitance-voltage of 100MeV O7+ ion irradiated transistor were studied before and after irradiation. The device was decapped and the electrical characterizations were performed at room temperature. Base current is observed to be more sensitive than collector current and gain appears to be degraded with ion fluence, also considerable degradation in C-V characteristics is observed and doping concentration is found to be increased along with the increase in ion fluence.

  3. Production of Highly Polarized Positrons Using Polarized Electrons at MeV Energies

    Science.gov (United States)

    Abbott, D.; Adderley, P.; Adeyemi, A.; Aguilera, P.; Ali, M.; Areti, H.; Baylac, M.; Benesch, J.; Bosson, G.; Cade, B.; Camsonne, A.; Cardman, L. S.; Clark, J.; Cole, P.; Covert, S.; Cuevas, C.; Dadoun, O.; Dale, D.; Dong, H.; Dumas, J.; Fanchini, E.; Forest, T.; Forman, E.; Freyberger, A.; Froidefond, E.; Golge, S.; Grames, J.; Guèye, P.; Hansknecht, J.; Harrell, P.; Hoskins, J.; Hyde, C.; Josey, B.; Kazimi, R.; Kim, Y.; Machie, D.; Mahoney, K.; Mammei, R.; Marton, M.; McCarter, J.; McCaughan, M.; McHugh, M.; McNulty, D.; Mesick, K. E.; Michaelides, T.; Michaels, R.; Moffit, B.; Moser, D.; Muñoz Camacho, C.; Muraz, J.-F.; Opper, A.; Poelker, M.; Réal, J.-S.; Richardson, L.; Setiniyaz, S.; Stutzman, M.; Suleiman, R.; Tennant, C.; Tsai, C.; Turner, D.; Ungaro, M.; Variola, A.; Voutier, E.; Wang, Y.; Zhang, Y.; PEPPo Collaboration

    2016-05-01

    The Polarized Electrons for Polarized Positrons experiment at the injector of the Continuous Electron Beam Accelerator Facility has demonstrated for the first time the efficient transfer of polarization from electrons to positrons produced by the polarized bremsstrahlung radiation induced by a polarized electron beam in a high-Z target. Positron polarization up to 82% have been measured for an initial electron beam momentum of 8.19 MeV /c , limited only by the electron beam polarization. This technique extends polarized positron capabilities from GeV to MeV electron beams, and opens access to polarized positron beam physics to a wide community.

  4. The KAERI 10 MeV Electron Linac - Description and Operational Manual

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Cheol; Park, Seong Hee; Jung, Young Uk; Han, Young Hwan; Kang, Hee Young

    2005-06-15

    The objective of this technical report is to guide the right operation and maintenance of the KAERI electron linac system. The KAERI electron linac system consists of 2 MeV injector based on 176 MHz Normal conducting RF (Radio Frequency)cavity and 10 MeV main accelerator based on 352 MHz Superconducting RF cavity, electron beamlines (injection and extraction). Since a electron accelerator generates hazard radiation, this system is located at the shielded room in basement and we can operate the system using the remote control system. It includes the description and the operational manual as well as the detailed technical direction for trouble shooting.

  5. Design of the MYRRHA 17-600 MeV Superconducting Linac

    CERN Document Server

    Biarrotte, J-L; Bouly, F; Carneiro, J-P; Vandeplassche, D

    2013-01-01

    The goal of the MYRRHA project is to demonstrate the technical feasibility of transmutation in a 100MWth Accelerator Driven System (ADS) by building a new flexible irradiation complex in Mol (Belgium). The MYRRHA facility requires a 600 MeV accelerator delivering a maximum proton flux of 4 mA in continuous operation, with an additional requirement for exceptional reliability. This paper will briefly describe the beam dynamics design of the main superconducting linac section which covers the 17 to 600 MeV energy range and requires enhanced fault-tolerance capabilities.

  6. The physics design of magnet in 14 MeV cyclotron

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The 14 MeV, 400 μA compact cyclotron is under construction at China Institute of Atomic Energy (CIAE). The design of main magnet and the result of beam dynamics in the cyclotron will be described in this paper, including the choice of main parameters of magnet, the method of shimming isochronous field in the compact cyclotron and optimization of the magnetic field in central region. The beam will be accelerated to 14.6 MeV by optimizing the magnet structure.

  7. Design and experiment of insulation support of 2 MeV injector

    CERN Document Server

    Wang Meng; Dai Guang Sen; Wang Jing Sheng; Xia Lian Sheng; Huang Hai Bo

    2002-01-01

    Aiming at the technical request of high power injector, the authors designed two Nylon radial graded insulation supports on the heads of cathode and anode of the existing 2 MeV injector. The experiment results showed that, on the basis of credible insulation, the supports improved the quality of coaxiality between the cathode and the anode, ameliorated the identity of the three axes of beams, magnetic field and mechanism, and settled the groundwork for advancing each technical performances of the 2 MeV injector

  8. Design of an MeV ultra-fast electron diffraction experiment at Tsinghua university

    Institute of Scientific and Technical Information of China (English)

    LI Ren-Kai; TANG Chuan-Xiang; HUANG Wen-Hui; DU Ying-Chao; SHI Jia-Ru; YAN Li-Xin

    2009-01-01

    Time-resolved MeV ultra-fast electron difiraction(UED)is a powerful tool for structure dynamics studies.In this paper.we present a design of a MeV UED facility based on a photocathode RF gun at Tsinghua University.Electron beam qualities are optimized with numerical simulations,indicating that resolutions of 250 fs and 0.01 A.and bunch charge exceeding 105 electrons are expected with technically achievable machine parameters.Status of experiment preparation is also presented.

  9. Radiation hardness of a single crystal CVD diamond detector for MeV energy protons

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Yuki, E-mail: y.sato@riken.jp [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Shimaoka, Takehiro; Kaneko, Junichi H. [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628 (Japan); Murakami, Hiroyuki [The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Isobe, Mitsutaka; Osakabe, Masaki [National Institute for Fusion Science, 322-6, Oroshi-cho Toki-city, Gifu 509-5292 (Japan); Tsubota, Masakatsu [Graduate School of Engineering, Hokkaido University, N13, W8, Sapporo 060-8628 (Japan); Ochiai, Kentaro [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Chayahara, Akiyoshi; Umezawa, Hitoshi; Shikata, Shinichi [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan)

    2015-06-01

    We have fabricated a particle detector using single crystal diamond grown by chemical vapor deposition. The irradiation dose dependence of the output pulse height from the diamond detector was measured using 3 MeV protons. The pulse height of the output signals from the diamond detector decreases as the amount of irradiation increases at count rates of 1.6–8.9 kcps because of polarization effects inside the diamond crystal. The polarization effect can be cancelled by applying a reverse bias voltage, which restores the pulse heights. Additionally, the radiation hardness performance for MeV energy protons was compared with that of a silicon surface barrier detector.

  10. Beam Loss by Lorentz Stripping in a 100 MeV Compact H~- Cyclotron

    Institute of Scientific and Technical Information of China (English)

    Larry; Root

    2002-01-01

    The success of TRIUMF’s ISAC facility demonstrates that a 500 MeV 100 μ A H cyclotron is agood choice for the driver stage of an ISOL type RIB facility. As a result, China Institute of AtomicEnergy is proposing the construction of a 75~100 MeV 200~500μA H~- cyclotron as an upgrade to theBeijing Tandem Laboratory. This would be a multiple user facility, which would include a RIB target

  11. Effects of 3 MeV proton irradiation on the mechanical properties of polyimide films

    Science.gov (United States)

    Hill, David J. T.; Hopewell, Jefferson L.

    1996-11-01

    The effects of 3 MeV proton irradiation on the elongation to break, fracture energy and Young's Modulus have been investigated for films of Kapton and Ultem over the dose range 0-75 MGy at ambient temperature. The results have been compared with those reported by other workers for irradiation by 60Co gamma rays and 2 MeV electron beams under similar conditions, and little difference was found between the damage to the mechanical properties of the films induced by these three beam types.

  12. (π+/-,2N) reactions at 165 and 245 MeV

    Science.gov (United States)

    Altman, A.; Ashery, D.; Piasetzky, E.; Lichtenstadt, J.; Yavin, A. I.; Bertl, W.; Felawka, L.; Walter, H. K.; Powers, R. J.; Winter, R. G.; Pluym, J. V. D.

    1986-11-01

    The (π+,2p) and (π+/-, pn) reactions were studied by coincidence detection of the outgoing nucleons on C, Fe, and Bi at 165 and 245 MeV and on 16O and 18O at 165 MeV. The quasideuteron component is identified and found to account for only about 10% of the absorption cross section for carbon down to about 2% for bismuth. With corrections for the final-state interaction of outgoing nucleons it amounts to at most 40%. The data indicate that quasideuteron absorption following pion scattering is not likely. The absorption on T=1 nucleon pairs is about 4% of that on quasideuterons.

  13. Properties of the {sup 12}C 10 MeV state determined through {beta}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Diget, C.A. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Barker, F.C. [Department of Theoretical Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 (Australia); Borge, M.J.G. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Cederkaell, J. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Fedosseev, V.N. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Fraile, L.M. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Fulton, B.R. [Department of Physics, University of York, Heslington, YO10 5DD (United Kingdom); Fynbo, H.O.U. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark)]. E-mail: fynbo@phys.au.dk; Jeppesen, H.B. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Jonson, B. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Koester, U. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Meister, M. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Nilsson, T. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Nyman, G. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Prezado, Y. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Riisager, K. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Rinta-Antila, S. [Department of Physics, University of Jyvaeskylae, FIN-40351 Jyvaeskylae (Finland); Tengblad, O. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Turrion, M. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Wilhelmsen, K. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Aeystoe, J. [Department of Physics, University of Jyvaeskylae, FIN-40351 Jyvaeskylae (Finland); Helsinki Institute of Physics, University of Helsinki, FIN-00014 Helsinki (Finland)

    2005-10-03

    The {beta}-delayed triple-{alpha} particle decay of {sup 12}B has been measured with a setup that favours coincidence detection. A broad state in {sup 12}C, previously reported around 10 MeV, has been seen and its properties determined through R-matrix analysis of the excitation spectrum. The spin and parity are 0{sup +}. Interference between this state and the Hoyle state at 7.654 MeV has a marked influence on the spectrum. The coupling between the two states makes it difficult to determine the resonance energy.

  14. Pionic charge exchange on the proton from 40 to 250 MeV

    Science.gov (United States)

    Breitschopf, J.; Bauer, M.; Clement, H.; Cröni, M.; Denz, H.; Friedman, E.; Gibson, E. F.; Meier, R.; Wagner, G. J.

    2006-08-01

    The total cross sections for pionic charge exchange on hydrogen were measured using a transmission technique on thin CH2 and C targets. Data were taken for π- lab energies from 39 to 247 MeV with total errors of typically 2% over the Δ-resonance and up to 10% at the lowest energies. Deviations from the predictions of the SAID phase shift analysis in the 60-80 MeV region are interpreted as evidence for isospin-symmetry breaking in the s-wave amplitudes. The charge dependence of the Δ-resonance properties appears to be smaller than previously reported.

  15. Neutron field measurements at the 590 MeV ring cyclotron of the Paul Scherrer Institute

    CERN Document Server

    Grecescu, M; Boschung, M; Fiechtner, A; Gmuer, K; Laedermann, J P; Valley, J F; Wernli, C

    2002-01-01

    A complete characterization of the neutron field was performed at 3 representative areas around the 590 MeV Ring cyclotron of the Paul Scherrer Institute. The neutron spectra were measured with a Bonner spheres system, sup 2 sup 0 sup 9 Bi and sup 2 sup 3 sup 2 Th fission track detectors. Their shapes are very different according to the location; neutron energies up to about 200 MeV were recorded. The dosimetry was performed with various active instruments: 2202D, LB 6411, LINUS, nm 500, nm 500X, HANDI, REM 500. The comparison between the H*(10) values determined by different systems is presented and discussed.

  16. The response of the Sievert instrument in neutron beams up to 180 MeV

    CERN Document Server

    Kylionen, J E; Samuelson, G

    2001-01-01

    Measurements with a tissue-equivalent proportional counter (TEPC) using the variance-covariance method have been performed in neutron beams between 71 keV and 180 MeV and in the cosmic radiation reference field (CERF) at CERN. The results show that with appropriate linear Q/sub D/(y/sub D/) relations, the ambient dose equivalent can be determined within about 55% in these beams. Build- up measurements show that wall thickness is not crucial for H* determinations at 60 and 180 MeV. (26 refs).

  17. Thin Object Radiography with a 2.2 MeV Pulsed Power Machine

    Science.gov (United States)

    Haines, Todd; Danielson, Jeremy; Wood, W. Monty

    2015-06-01

    An experimental series was performed at a pulsed-power 2.2 MeV flash radiography machine to determine the lower limits of its mass sensitivity. This machine uses a rod-pinch diode with accelerating potential of 2.2 MeV and 50 ns pulse duration. Tungsten, aluminum, and titanium rod anodes were used to tune the emitted bremsstrahlung spectrum; as well as aluminum and beryllium filter materials. Analysis of thin tantalum foils shows a mass sensitivity as low as 300 μg/cm2. This is a factor of 5 better than previous measurements.

  18. Reactions sup 58,64 Ni( p ,. pi. sup + ) at 201 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Badala, A.; Barbera, R.; Palmeri, A.; Pappalardo, G.S.; Bonasera, A. (Istituto Nazionale di Fisica Nucleare, Corso Italia 57, 95129 Catania (Italy)); Riggi, F.; Adorno, A. (Istituto Nazionale di Fisica Nucleare and Dipartimento di Fisica dell' Universita di Catania, Corso Italia 57, 95129 Catania (Italy)); Bimbot, L. (Institut de Physique Nucleaire, Boite Postale 1, 91406 Orsay CEDEX (France))

    1992-08-01

    The production of positive and negative pions induced by 201 MeV protons on {sup 58}Ni and {sup 64}Ni isotopes has been studied. The double differential cross sections have been measured at the laboratory angles 22{degree}, 35{degree}, 55{degree}, 72{degree}, 90{degree}, 105{degree}, 120{degree}, 138{degree}, 155{degree} and from 20 MeV kinetic energy up to the kinematical limit. Features of the double differential cross sections relative to the two targets are discussed and compared to results obtained at higher incident energies.

  19. 16O+12C resonances within the strong absorption region for Ec.m.>23 MeV

    Science.gov (United States)

    Jachcinski, C. M.; Braun-Munzinger, P.; Berkowitz, G. M.; Freifelder, R. H.; Gai, M.; Renner, T. R.; Uhlhorn, C. D.

    1980-07-01

    Excitation functions for 12C(16O, 16O)12C elastic and inelastic scattering have been measured in the energy range 23<=Ec.m.<=32 MeV. Two strong structures at Ec.m.=25.5 and 29.6 MeV are observed in the 12C + 16O(3-,6.13 MeV) exit channel; angular correlation measurements at these energies suggest spin assignments of 15- and 16+, respectively. NUCLEAR REACTIONS 12C(16O, 16O*)12C*; Ec.m.=23-32 MeV, θc.m.(16O)=130°-155° measured σ(E) angular correlations.

  20. The design study for a 500 MeV proton synchrotron with CSNS linac as an injector

    CERN Document Server

    Huang, Liang-Sheng; Ji, Hong-Fei

    2016-01-01

    Using the China Spallation Neutron Source (CSNS) linac as the injector, a 500 MeV proton synchrotron is proposed for multidisciplinary application, such as biology, material and proton therapy. The synchrotron will deliver proton beam with energy from 80 MeV to 500 MeV. A compact lattice design was worked out, and all the important beam dynamics issues were investigated. The 80 MeV H- beam is stripped and injected into the synchrotron by using multi-turn injection. In order to continuously extraction the proton with small beam loss, the achromatic structure is proposed and slow extraction method with RF knock-out is adopted and optimized.

  1. Measurement of thick target neutron yields for protons and deuterons in Ten's of MeV region

    Energy Technology Data Exchange (ETDEWEB)

    Baba, M.; Aoki, T.; Kawata, N.; Hagiwara, M.; Miura, T.; Yamadera, A.; Yonai, S.; Nakamura, T. [Tohoku Univ., Sendai (Japan)

    2002-07-01

    We have measured energy-angular differential thick target neutron yields (TTY) for C, Al, Ta, W(p,n) reactions at 50 MeV, and Li, Be (d,n) reactions for 25 MeV deuterons with the TOF method using Tohoku University K=110 MeV cyclotron equipped with a beam swinger system and a well collimated TOF line. Neutron spectrum data have been obtained down to {approx} 0.8 MeV from the highest energy at several laboratory angles from 0-deg to 90-deg. The results are compared with other experiments and a recent data library LA-150.

  2. Optimal Design of Proposed 800 MeV Proton Cyclotron Beam Dynamics

    Institute of Scientific and Technical Information of China (English)

    YANG; Jian-jun; LI; Ming; ZHANG; Tian-jue; SONG; Guo-fang; AN; Shi-zhong

    2015-01-01

    The high intensity beam dynamic simulation shows that the theoretic beam current limit of the original design version of the 800 MeV proton cyclotron CYCIEA-800is 1mA.In order to further improve the current limit and reduce beam losses in the cyclotron,the layout of the cyclotron

  3. Voltage holding study of 1 MeV accelerator for ITER neutral beam injector.

    Science.gov (United States)

    Taniguchi, M; Kashiwagi, M; Umeda, N; Dairaku, M; Takemoto, J; Tobari, H; Tsuchida, K; Yamanaka, H; Watanabe, K; Kojima, A; Hanada, M; Sakamoto, K; Inoue, T

    2012-02-01

    Voltage holding test on MeV accelerator indicated that sustainable voltage was a half of that of ideal quasi-Rogowski electrode. It was suggested that the emission of the clumps is enhanced by a local electric field concentration, which leads to discharge initiation at lower voltage. To reduce the electric field concentration in the MeV accelerator, gaps between the grid supports were expanded and curvature radii at the support corners were increased. After the modifications, the accelerator succeeded in sustaining -1 MV in vacuum without beam acceleration. However, the beam energy was still limited at a level of 900 keV with a beam current density of 150 A∕m(2) (346 mA) where the 3 × 5 apertures were used. Measurement of the beam profile revealed that deflection of the H(-) ions was large and a part of the H(-) ions was intercepted at the acceleration grid. This causes high heat load on the grids and the breakdowns during beam acceleration. To suppress the direct interception, new grid system was designed with proper aperture displacement based on a 3D beam trajectory analysis. As the result, the beam deflection was compensated and the voltage holding during the beam acceleration was improved. Beam parameter of the MeV accelerator was increased to 980 keV, 185 A∕m(2) (427 mA), which is close to the requirement of ITER accelerator (1 MeV, 200 A∕m(2)).

  4. Experimental bremsstrahlung yields for MeV proton bombardment of beryllium and carbon

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, David D. [Institute for Environmental Research, Australian Nuclear Science and Technology Organisation, Private Mail Bag 1, Menai, NSW 2234 (Australia)], E-mail: dcz@ansto.gov.au; Stelcer, Eduard; Siegele, Rainer; Ionescu, Mihail; Prior, Michael [Institute for Environmental Research, Australian Nuclear Science and Technology Organisation, Private Mail Bag 1, Menai, NSW 2234 (Australia)

    2008-04-15

    Experimental bremsstrahlung yields for 2, 3 and 4 MeV protons on thin beryllium and carbon targets have been measured. The yields have been corrected for detector efficiency, self-absorption in the target and fitted to 9th order polynomials over the X-ray energy range 1-10 keV for easy comparison with theoretical calculations.

  5. 10MeV/20kW Electron Linac for Irradiation Microwave System

    Institute of Scientific and Technical Information of China (English)

    WU; Qing-feng; ZHU; Zhi-bin; WANG; Xiu-long; LIU; Bao-jie; HU; Tao

    2015-01-01

    Microwave system is one of main subsystems of 10 MeV/20kW electron irradiating linac.It provides accelerating tube with microwave power,and accelerates electron beam to design energy,high-energy electron beam is ultimately used for irradiation processing.In order to meet the requirements of the

  6. Praseodymium activation detector for measuring bursts of 14 MeV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Meehan, Tim, E-mail: meehanbt@nv.doe.go [National Security Technologies, LLC, P.O. Box 98521, North Las Vegas, NV 89030 (United States); Hagen, E.C. [National Security Technologies, LLC, P.O. Box 98521, North Las Vegas, NV 89030 (United States); Ruiz, C.L.; Cooper, G.W. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185 (United States)

    2010-08-21

    A new, accurate, neutron activation detection scheme for measuring pulsed neutrons has been designed and tested. The detection system is sensitive to neutrons with energies above 10 MeV; importantly, it is insensitive to gamma radiation <10 MeV and to lower-energy (e.g., fission and thermal) neutrons. It is based upon the use of {sup 141}Pr, an element that has a single, naturally occurring isotope, a significant n,2n cross-section, and decays by positron emission that result in two coincident 511 keV photons. Neutron fluences are thus inferred by relating measured reaction product decay activity to fluence. Specific sample activity is measured using the sum-peak method to count gamma-ray coincidences from the annihilation of the positron decay products. The system was tested using 14 and 2.45 MeV neutron bursts produced by NSTec Dense Plasma Focus Laboratory fusion sources. Lead, copper, beryllium, and silver activation detectors were compared. The detection method allows measurement of 14 MeV neutron yield with a total error of {approx}18%.

  7. The pilot experimental study of 14 MeV fast neutron digital radiography

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    14 MeV Fast neutrons has good penetrability and the 14 MeV fast neutron radiography can meet the need of Non-Destructive Test of the structure and lacuna of heavy-massive sample, whose shell is made of heavy metal and in which there are some hydrogen materials, and the study of fast neutron digital radiography just begins in China. By the use of a D-T accelerator, a digital imaging system made up of a fast neutron scintillation screen made of ZnS(Ag) and polypropylene, lens and a scientific grade CCD, the experimental study of fast neutron radiography has been done between 4.3×1010-6.8×1010 n/s of neutron yield. Some 14 MeV fast neutron digital radiographs have been gotten. According to experimental radiographs and their data, the performance of the fast neutron scintillation screen and the basic characters of 14 MeV fast neutron radiography are analyzed, and it is helpful for the further research.

  8. Multi-turn injection of 50 MeV protons into the CERN Proton Synchrotron booster

    CERN Document Server

    Raginel, V; Carli, C; Mikulec, B

    2013-01-01

    Since 1978, Linac2 produces beams of 50 MeV protons with a current around 160 mA, which are injected into the CERN Proton Synchrotron Booster (PSB) with conventional multi-turn injection using a horizontal septum. It is planned to replace Linac2 during a future long stop with a new H- linac, Linac4, injecting at higher energy (160 MeV) and making use of the modern chargeexchange injection principle. Due to the age of Linac2 and to a delicate vacuum situation the risk of a serious Linac2 breakdown has to be considered. Therefore it is necessary to study if the PSB could produce beams useful for the LHC and other experiments injecting a Linac4 proton beam at 50 MeV with much lower average current compared to Linac2 and without the need for a long installation of the 160 MeV H- injection hardware. Benchmarking of the PSB injection model with the existing injection system with Linac2 using the ORBIT code has been done for a LHC-type beam and then the injection model was used to estimate the brightness for LHC-typ...

  9. Multi-turn injection of 50 MeV protons into the CERN Proton Synchrotron Booster

    CERN Document Server

    Raginel, V; Carli, C; Mikulec, B

    2013-01-01

    Since 1978, Linac2 produces beams of 50 MeV protons with a current around 160 mA, which are injected into the CERN Proton Synchrotron Booster (PSB) with conventional multi-turn injection using a horizontal septum. It is planned to replace Linac2 during a future long stop with a new H- linac, Linac4, injecting at higher energy (160 MeV) and making use of the modern chargeexchange injection principle. Due to the age of Linac2 and to a delicate vacuum situation the risk of a serious Linac2 breakdown has to be considered. Therefore it is necessary to study if the PSB could produce beams useful for the LHC and other experiments injecting a Linac4 proton beam at 50 MeV with much lower average current compared to Linac2 and without the need for a long installation of the 160 MeV H- injection hardware. Benchmarking of the PSB injection model with the existing injection system with Linac2 using the ORBIT code has been done for a LHC-type beam and then the injection model was used to estimate the brightness for LHC-typ...

  10. NUSTAR, SWIFT, and GROND Observations of the Flaring MEV Blazar PMN J0641-0320

    DEFF Research Database (Denmark)

    Ajello, M.; Ghisellini, G.; Paliya, V. S.;

    2016-01-01

    Area Telescope and subsequent follow-up observations with NuSTAR, Swift, and GROND of a new member of the MeV blazar family: PMN J0641-0320. Our optical spectroscopy provides confirmation that this is a flat-spectrum radio quasar located at a redshift of z = 1.196. Its very hard NuSTAR spectrum (power...

  11. Positronium formation in helium bubbles in 600 MeV proton-irradiated aluminium

    DEFF Research Database (Denmark)

    Jensen, K. O.; Eldrup, Morten Mostgaard; Singh, Bachu Narain

    1985-01-01

    Aluminium samples containing helium bubbles produced by 600 MeV proton irradiation at 430°C were investigated by positron annihilation; both lifetime and angular correlation measurements were made. The angular correlation curves contain an unusually narrow component. This component is associated...

  12. Production of positive pions by 800 MeV protons on carbon

    Science.gov (United States)

    Denes, Peter; Dieterle, B. D.; Wolfe, D. M.; Bowles, T.; Dombeck, T.; Simmons, J. E.; Bhatia, T. S.; Glass, G.; Tippens, W. B.

    1983-03-01

    The double differential cross section for the reaction p+C-->π++X has been measured at laboratory angles of 7°, 15°, 20°, and 30°. NUCLEAR REACTIONS E=800 MeV, p+12C-->π++X measured dσdEπ for θπ=7°, 15°, 20°, 30°.

  13. The neutron-deuteron elastic scattering angular distribution at 95 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Mermod, Philippe

    2004-04-01

    The neutron-deuteron elastic scattering differential cross section has been measured at 95 MeV incident neutron energy, with the Medley setup at TSL in Uppsala. The neutron-proton differential cross section has also been measured for normalization purposes. The data are compared with theoretical calculations to investigate the role of three-nucleon force effects.

  14. Measurements of the analyzing power of elastic pd-scattering at 190 MeV

    NARCIS (Netherlands)

    Seip, M; Bieber, R; Drentje, AG; van Goethem, MJ; Harakeh, MN; Hoefman, M; Huisman, H; Kalantar-Nayestanaki, N; Kremers, HR; Messchendorp, JG; Volkerts, M; van der Werf, SY; Wilschut, HW; Desplanques, B; Protasov, K; SilvestreBrac, B; Carbonell, J

    1999-01-01

    A beam-polarimeter for medium energy protons and deuterons (E=100-200 MeV) has been constructed. Its operation is based on the p + d, p + p and d + p elastic scattering with coincident detection of both particles in 4 independent planes. The 16 detectors of the polarimeter have a phoswich constructi

  15. Scale size of magnetic turbulence in tokamaks probed with 30-MeV electrons

    NARCIS (Netherlands)

    Entrop, I.; Cardozo, N. J. L.; R. Jaspers,; Finken, K.H.

    2000-01-01

    Measurements of synchrotron radiation emitted by 30-MeV runaway electrons in the TEXTOR-94 tokamak show that the runaway population decays after switching on neutral beam injection (NBI). The decay starts only with a significant delay, which decreases with increasing NBI heating power. This delay pr

  16. Response of LaBr{sub 3}(Ce) scintillators to 14 MeV fusion neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Cazzaniga, C., E-mail: carlo.cazzaniga@mib.infn.it [University of Milano Bicocca, Departement of Physics, Piazza della Scienza 3, Milano 20125 (Italy); Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano 20125 (Italy); Nocente, M. [University of Milano Bicocca, Departement of Physics, Piazza della Scienza 3, Milano 20125 (Italy); Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano 20125 (Italy); Tardocchi, M. [Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano 20125 (Italy); Rebai, M. [University of Milano Bicocca, Departement of Physics, Piazza della Scienza 3, Milano 20125 (Italy); Pillon, M. [Associazione EURATOM-ENEA sulla Fusione ENEA C.R. Frascati, Via E. Fermi, 45, 00044 Frascati, Roma (Italy); Camera, F.; Giaz, A.; Pellegri, L. [University of Milano, Departement of Physics, Via Celoria 16, Milano 1-20133 (Italy); Gorini, G. [University of Milano Bicocca, Departement of Physics, Piazza della Scienza 3, Milano 20125 (Italy); Istituto di Fisica del Plasma, Associazione EURATOM-ENEA-CNR, via Roberto Cozzi 53, Milano 20125 (Italy)

    2015-04-01

    The response of a 3″×3″ LaBr{sub 3}(Ce) scintillator to 14 MeV neutron irradiation has been measured at the Frascati Neutron Generator and simulated by means of a dedicated MCNP model. Several reactions are found to contribute to the measured response, with a key role played by neutron inelastic scattering and (n,2n) reactions on {sup 79}Br, {sup 81}Br and {sup 139}La isotopes. An overall 43% efficiency to 14 MeV neutron detection above an experimental threshold of 0.35 MeV is calculated and confirmed by measurements. Post irradiation activation of the crystal has been also observed and is explained in terms of nuclear decays from the short lived {sup 78}Br and {sup 80}Br isotopes produced in (n,2n) reactions. The results presented in this paper are of relevance for the design of γ-ray detectors in burning plasma fusion experiments of the next generation, such as ITER, where capability to perform measurements in an intense 14 MeV neutron flux is required.

  17. Lead 207, 208 (n, xn gamma) reactions for neutron energies up to 200 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Pavlik, A.; Vonach, H. [Univ. Wien (Austria). Inst. fuer Radiumforschung und Kernphysik; Chadwick, M.B.; Haight, R.C.; Nelson, R.O.; Wender, S.A.; Young, P.G. [Los Alamos National Lab., NM (United States)

    1994-07-01

    High-resolution {gamma}-ray spectra from the interaction of neutrons in the energy range from 3 to 200 MeV with {sup 207,208}Pb were measured with the white neutron source at the WNR facility at Los Alamos National Laboratory. From these data, excitation functions for prominent {gamma} transitions in {sup 200,202,204,206,207,208}Pb were derived from threshold to 200 MeV incident neutron energy. These {gamma}-production cross sections represent formation cross sections for excited states of the residual nuclei. The results are compared with the predictions of nuclear reaction calculations based on the exciton model for precompound emission, the Hauser-Feshbach theory for compound nuclear decay, and coupled channels calculations to account for direct excitation of collective levels. Good agreement was obtained over the entire energy range covered in the experiment with reasonable model parameters. The results demonstrate that multiple preequilibrium emission has to be taken into account above about 40 MeV, and that the level density model of Ignatyuk should be used instead of the Gilbert-Cameron and back-shifted Fermi-gas models if excitation energies exceed about 30 MeV.

  18. Stopping power of aluminium for 5-12 MeV protons and deuterons

    DEFF Research Database (Denmark)

    Andersen, H.H.; Garfinkel, A.F.; Hanke, C.C.;

    1966-01-01

    The stopping power of aluminium for 5-12 MeV protons and deuterons has been measured by a thermometric compensation technique working at liquid helium temperature. The experimental method is described and the standard deviation of the results is found to be 0.3%. In order to obtain this accuracy...

  19. Response of MEDEA BaF 2 detectors to 20-280 MeV photons

    Science.gov (United States)

    Bellia, G.; Alba, R.; Coniglione, R.; Del Zoppo, A.; Finocchiaro, P.; Maiolino, C.; Migneco, E.; Piattelli, P.; Sapienza, P.; Frascaria, N.; Lhenry, I.; Roynette, J. C.; Suomijärvi, T.; Alamanos, N.; Auger, F.; Gillibert, A.; Pierroutsakou, D.; Sida, J. L.; Silveira Gomes, P. R.

    1993-05-01

    The response function of MEDEA BaF 2 crystals to high energy photons, up to 280 MeV, has been studied using monochromatic γ-rays from the in flight annihilation of positron beams. The experimental response functions are compared to the results of Monte Carlo simulations based on the EGS3 code and parametrized over the whole investigated energy range.

  20. POSITRON-ELECTRON DECAY OF SI-28, AT AN EXCITATION-ENERGY OF 50-MEV

    NARCIS (Netherlands)

    BUDA, A; BACELAR, JC; BALANDA, A; VANDERPLOEG, H; SUJKOWSKI, Z; VANDERWOUDE, A

    1993-01-01

    The electron-positron pair decay of Si-28 at 50 MeV excitation produced by the isospin T=0 (alpha + Mg-24) and the mixed isospin T=0,1 (He-3 + Mg-25) reactions has been studied using a special designed Positron-Electron pair spectrometer PEPSI.

  1. A study of proton-induced reactions at 190 MeV

    NARCIS (Netherlands)

    Mukherjee, B.; Bacelar, J.C.S; Beijers, J.P.M.; Harakeh, M.N.; Kalantar-Nayestanaki, N.; Kis, M.; Löhner, H.; Mahjour Shafiei, M.

    2004-01-01

    Differential cross-sections and proton multiplicities, resulting from the bombardment of Fe-56, Pb-208, and U-238 targets by a 190 MeV proton beam were measured for the first time. Data were taken over two different angular ranges 5degrees-30degrees and 91degrees-160degrees with two different detect

  2. Nuclear data measurements for 40-90 MeV neutrons at TIARA

    Energy Technology Data Exchange (ETDEWEB)

    Baba, M. [Tohoku Univ., Sendai (Japan). Cyclotron and Radioisotope Center

    2000-03-01

    Experimental activities at the {sup 7}Li neutron source of TIARA, Japan Atomic Energy Research Institute, Takasaki Establishment are reviewed briefly. Experiments on (1) double-differential charged particle production cross sections for 40-90 MeV neutrons and protons, and (2) neutron elastic scattering and non-elastic cross sections are described as well as the frame of the research. (author)

  3. Design of a 10 MeV, 352.2 MHz drift tube Linac

    Indian Academy of Sciences (India)

    Nita S Kulkarni

    2012-08-01

    A conventional 10 MeV drift tube Linac is designed as a part of the - front end accelerator system for the future Indian Spallation Neutron Source. The front end Linac consists of a 50 keV H- ion source, low energy beam transport (LEBT), a 3 MeV radio frequency quadrupole (RFQ), and a 10 MeV drift tube Linac (DTL), which will be operated at 1.25% duty factor. Cell geometry of the DTL is optimized to house quadrupole magnets and to get maximum effective shunt impedance. Transmission efficiency and various other output parameters depend on the input design parameters. Beam dynamic studies are done to maximize the transmission efficiency with minimum emittance growth. Errors in the alignment of the quadrupoles inside the drift tubes or the DTL tank alignment with respect to transport line will degrade the beam quality and may reduce the transmission efficiency. Error study is performed to assess the acceptable tolerances on various parameters. This paper describes the 2D and 3D electromagnetic and beam dynamics simulations of the 352.2 MHz, 10 MeV drift tube Linac. Details of the DTL design are reported in this paper.

  4. Design of 7 MeV electron beams for breast radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jon In; Kim, Jung In; Kwon, Hyuck Jun [Interdisplinary Program in Radiation Applied Life Science, Seoul National University Graduate School, Seoul (Korea, Republic of); Ha, Sung Whan; Kim, Il Han [Dept. of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Hyun Suk; Ye, Sung Joon [Program in Biomedical Radiation Sciences, Dept. of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul (Korea, Republic of)

    2013-04-15

    For treating early stage breast cancer, breast conserving therapy with lumpectomy followed by radiation therapy has been preferred as the standard method Irradiation technique consists of whole breast irradiation of 50.0 Gy and supplemental boost of 10 Gy to the tumor bed. The 'boost' to supplement the dose to the highest risk breast tissue around the lumpectomy following whole breast irradiation (WBI) improves in-breast local control. Electron beams have been favored radiation as boost irradiation. Because of limited depth in electron beams, it is possible to reduce the dose for unwished organ such as lung and heart in located in deeper region. Traditionally, electron beams can be modified using a bolus. The use of bolus conforms 90% isodose curve of a single energy electron beam to the distal edge of the target volume. However, it often increases the skin dose with electron beams of energy below 10 MeV. Therefore, with an aim to simultaneously control the penetration depth of the electron beams and the skin dose, we produced the new 7 MeV electron beam by modulating 9 MeV electron beams available in clinical linear accelerators. In this study, we show that the 7 MeV electron beam is appropriate for treatment of patient with a tumor bed located in clinical depth (R90 – R80)

  5. DPA damage analysis for 14-MeV neutrons on PFC materials

    Science.gov (United States)

    Kim, Dong-woo; Lee, Bo-young; Ko, Seung-kook; Kim, Hee-soo; Noh, Seung-jung

    2015-06-01

    The dpa (displacement per atom) damage for 14-MeV neutron in a pfc materials was simulated using MCNPX/SPECTER code. The dpa values in the main components of the structural material SS316L, Fe, Cr and Ni, were calculated to analyze the effect of nuclear damage. According to the neutron wall load for ITER design base, a neutron flux of 3.5 × 1013 neutrons/cm2·sec was applied. The simulated dpa values were found to be as 3.0 dpa/fpy for Fe, 2.9 dpa/fpy for Cr and 3.1 dpa/fpy for Ni. For practical experiments, the simulated dpa values due to the irradiation damage of 17-MeV protons were found to be as 0.67 dpa at the peak and 0.05 at the surface for SS316L using by SRIM code at the same fluence. For the 17-MeV proton irradiation, the Bragg peak appears at a 0.64-mm depth. Also, SS316L specimens irradiated by a 17-MeV proton beam with a fluence of 1016 protons/cm2 were analyzed by using transmission electron microscopy.

  6. The 270 MeV deuteron beam polarimeter at the Nuclotron Internal Target Station

    Energy Technology Data Exchange (ETDEWEB)

    Kurilkin, P.K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Ladygin, V.P., E-mail: vladygin@jinr.ru [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Uesaka, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Suda, K. [RIKEN Nishina Center, Saitama (Japan); Gurchin, Yu.V.; Isupov, A.Yu. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Itoh, K. [Department of Physics, Saitama University, Saitama (Japan); Janek, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Physics Department, University of Zilina, 010 26 Zilina (Slovakia); Karachuk, J.-T. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Advanced Research Institute for Electrical Engineering, Bucharest (Romania); Kawabata, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Khrenov, A.N.; Kiselev, A.S.; Kizka, V.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kliman, J. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia); Krasnov, V.A.; Livanov, A.N. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute for Nuclear Research, Moscow (Russian Federation); Maeda, Y. [Kyushi University, Hakozaki (Japan); Malakhov, A.I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Matousek, V.; Morhach, M. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia)

    2011-06-21

    A deuteron beam polarimeter has been constructed at the Internal Target Station at the Nuclotron of JINR. The polarimeter is based on spin-asymmetry measurements in the d-p elastic scattering at large angles and the deuteron kinetic energy of 270 MeV. It allows to measure vector and tensor components of the deuteron beam polarization simultaneously.

  7. Simulation and Field Measurement of Quadrupole Magnets for KOMAC 20MeV Beam line

    Energy Technology Data Exchange (ETDEWEB)

    Chung, B. H.; Kim, H. S.; Song, Y. G.; Kwon, H. J.; Cho, Y. S. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, quadrupole magnets the same as installed at the beam line simulated and analyzed for magnetic fields. Also quadrupole magnets will be measured field stability and evaluated reliability on long time operation. Control system consisted of Labview program and communication method consisted of Ethernet and Rs-232 with optical fiber for devices safety from high voltage and/or high current. As a results the DC power supply is controlled, magnetic fields data is acquired and coil temperature is measured. Magnetic field with hall sensor and temperature with K-type thermo-couple are measured with conversion factor using by voltmeter. Korea Multi-purpose Accelerator Complex (KOMAC) was developed at Gyeongju in Korea in 2012. KOMAC including a 50-keV ion source, a 3-MeV RFQ, and a 100-MeV DTL. And beam line consists of 20-MeV and 100-MeV for user. Proton beam transferred from the linac to the beam line using by dipole magnets and transferred proton beam focused and decreased beam loss and by quadrupole magnets.

  8. The pilot experimental study of 14 MeV fast neutron digital radiography

    Institute of Scientific and Technical Information of China (English)

    TANG Bin; ZHOU ChangGen; HUO HeYong; WU Yang; LIU Bin; LOU BenChao; SUN Yong

    2009-01-01

    14 MeV Fast neutrons has good penetrability and the 14 MeV fast neutron radiography can meet the need of Non-Destructive Test of the structure and lacuna of heavy-massive sample,whose shell is made of heavy metal and in which there are some hydrogen materials,and the study of fast neutron digital radiography just begins in China.By the use of a D-T accelerator,a digital imaging system made up of a fast neutron scintillation screen made of ZnS(Ag) and polypropylene,lens and a scientific grade CCD,the experimental study of fast neutron radiography has been done between 4.3×1010-6.8×1010 n/s of neutron yield.Some 14 MeV fast neutron digital radiographs have been gotten.According to ex-perimental radiographs and their data,the performance of the fast neutron scintillation screen and the basic characters of 14 MeV fast neutron radiography are analyzed,and it is helpful for the further re-search.

  9. Integral cross sections for π+p scattering between 52 and 126 MeV

    Science.gov (United States)

    Friedman, E.; Goldring, A.; Wagner, G. J.; Altman, A.; Johnson, R. R.; Meirav, O.; Hanna, M.; Jennings, B. K.

    1989-11-01

    Integral cross sections for the elastic scattering of π+ on p from 20° and 30° to 180° were measured at seven energies between 52 and 126 MeV. These integrals are found to be in good agreement with predictions made with currently accepted phase shifts.

  10. Vector and tensor analyzing powers in deuteron-proton breakup at 130 MeV

    NARCIS (Netherlands)

    Stephan, E.; Kistryn, St.; Sworst, R.; Biegun, A.; Bodek, K.; Ciepal, I.; Deltuva, A.; Epelbaum, E.; Fonseca, A. C.; Golak, J.; Kalantar-Nayestanaki, N.; Kamada, H.; Kis, M.; Klos, B.; Kozela, A.; Mahjour-Shafiei, M.; Micherdzinska, A.; Nogga, A.; Skibinski, R.; Witala, H.; Wronska, A.; Zejma, J.; Zipper, W.

    2010-01-01

    High-precision data for vector and tensor analyzing powers for the (1)H((d) over right arrow, pp)n reaction at a 130-MeV deuteron beam energy have been measured over a large part of the phase space. Theoretical predictions based on various approaches to describe the three nucleon (3N) system reprodu

  11. Model independent optical potential for protons at 155 MeV

    Science.gov (United States)

    Brissaud, I.

    1981-06-01

    Using the model independent procedure, 155 MeV proton optical potentials are deduced from the elastic scattering data. The nuclear interior of these potentials are less attractative than predicted by a phenomenological potentials. A comparison is done with a self consistent meson model.

  12. I = 0 C = +1 mesons from 1920 to 2410 MeV

    CERN Document Server

    Anisovich, A V; Batty, C J; Bugg, D V; Hodd, C; Lu, H C; Nikonov, V A; Sarantsev, A V; Sarantsev, V V; Zou, B S; 10.1016/S0370-2693(00)01018-2

    2011-01-01

    A combined fit is presented to data on pbar-p annihilation in flight to final states eta-pizero-pizero, pizero-pizero, eta-eta, eta-etaprime and piminus-piplus. The emphasis lies in improving an earlier study of eta-pizero-pizero by fitting data at nine pbar momenta simultaneously and with parameters consistent with the two-body channels. There is evidence for all of the I=0, C=+ q-qbar states expected in this mass range. New resonances are reported with masses and widths M,Gamma as follows: JPC = 4^{-+} (2328+-38, Gamma=240+-90) MeV, 1^{++} (1971+-15, 240+-45) MeV, 0^{-+} (2285+-20, 325+-30) MeV, and 0^{-+} (2010 ^{+35}_{-60}, 270+-60) MeV. Errors on the masses and widths of other resonances are also reduced substantially. All states lie close to parallel straight line trajectories of excitation number v. mass squared.

  13. POSITRON-ELECTRON DECAY OF SI-28, AT AN EXCITATION-ENERGY OF 50-MEV

    NARCIS (Netherlands)

    BUDA, A; BACELAR, JC; BALANDA, A; VANDERPLOEG, H; SUJKOWSKI, Z; VANDERWOUDE, A

    1993-01-01

    The electron-positron pair decay of Si-28 at 50 MeV excitation produced by the isospin T=0 (alpha + Mg-24) and the mixed isospin T=0,1 (He-3 + Mg-25) reactions has been studied using a special designed Positron-Electron pair spectrometer PEPSI.

  14. Stopping powers for MeV Ge ions in Al foil

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Stopping powers for Ge ions (3.5MeV~8.0MeV) in Al foil were measured with RBS (Rutherford backscattering) technique and determined with a new method. Our results are much smaller than the values predicted by the TRIM code and LSS theory.

  15. Design of a 120 MeV $H^{-}$ Linac for CERN High-Intensity Applications

    CERN Document Server

    Gerigk, F

    2002-01-01

    The SPL (Superconducting Proton Linac) study at CERN foresees the construction of a 2.2 GeV linac as a high beam-power driver for applications such as a second-generation radioactive ion beam facility or a neutrino superbeam. At the same time such a high-performance injector would both modernize and improve the LHC injection chain. The 120 MeV normal-conducting section of the SPL could be used directly in a preliminary stage for H- charge-exchange injection into the PS Booster. This would increase the proton flux to the CERN experiments while also improving the quality and reliability of the beams for the LHC. The 120 MeV linac consists of a front-end, a conventional Drift Tube Linac (DTL) to 40 MeV and a Cell Coupled Drift Tube Linac (CCDTL) to the full energy. All the RF structures will operate at 352 MHz, using klystrons and RF equipment recovered from the LEP collider. This paper concentrates on the design of the 3 to 120 MeV section. It introduces the design criteria for high-stability beam optics and th...

  16. 22 MeV polarized proton scattering from 40Ca and effective NN interactions

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Analyzing powers and differential cross sections have been measured for elastic scattering of 22 MeV polarized protons from 40Ca, 16O and 12C, and diferential cross sections for inelastic scattering of 22 MeV protons from 3- (3.736 MeV)and 5-(4.491 MeV) states of 40Ca have also been measured. The experimental data for polarized proton elastic scattering have been analyzed with a phenomenological optical potential parameters, the experimental data and theoretical values are in good agreement. In the theoretical frame of microscopic single scattering model, transition densities extracted from electron inelastic scattering and M3Y and Halderson’s effective interactions have been utilized to analyze the experimental data of 22 MeV proton inelastic scattering from 40Ca. Overall, it seems that Halderson’s effective interaction can better describe the experimental data than M3Y although the degree of agreement between experimental and theoretical values needs to be improved.

  17. Defect microstructure in copper alloys irradiated with 750 MeV protons

    DEFF Research Database (Denmark)

    Zinkle, S.J.; Horsewell, A.; Singh, B.N.

    1994-01-01

    Transmission electron microscopy (TEM) disks of pure copper and solid solution copper alloys containing 5 at% of Al, Mn, or Ni were irradiated with 750 MeV protons to damage levels between 0.4 and 2 displacements per atom (dpa) at irradiation temperatures between 60 and 200 degrees C. The defect ...

  18. SPIN-ISOSPIN EXCITATIONS IN NUCLEI VIA (HE-3,T) REACTIONS AT 450 MEV

    NARCIS (Netherlands)

    FUJIWARA, M; AKIMUNE, H; DAITO, [No Value; EJIRI, H; FUJITA, Y; GREENFIELD, MB; HARAKEH, MN; HAZAMA, R; INOMATA, T; JANECKE, J; KUDOMI, N; KUME, K; NAKAYAMA, S; SHINMYO, K; TAMII, A; TANAKA, M; TOYOKAWA, H; YOSOI, M

    1994-01-01

    Spin-isospin excitations in nuclei havee been studied by means of the (He-3, t) reactions at 450 MeV. The Gamow-Teller (GT) resonances are found to be strongly excited. A fine structure of the giant Gamow Teller resonances in medium-heavy nuclei is observed with an energy resolution of 130 keV. The

  19. Measurement of 181 MeV H- ions stripping cross-sections by carbon stripper foil

    Science.gov (United States)

    Saha, P. K.; Yoshimoto, M.; Yamazaki, Y.; Hotchi, H.; Harada, H.; Okabe, K.; Kinsho, M.; Irie, Y.

    2015-03-01

    The stripping cross-sections of 181 MeV H- (negative hydrogen) ions by the carbon stripper foil are measured with good accuracy. The present experiment was carried out at the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex). The stripping cross-sections for different charge states, also known as electron loss cross-sections of H- ion, are denoted as σ-11, σ-10 and σ01, for both electrons stripping (H- →H+), one-electron stripping (H- →H0) and the 2nd-electron stripping (H0 →H+) proceeding σ-10, respectively. We have established very unique and precise techniques for such measurements so as also to determine a foil stripping efficiency very accurately. The cross-sections σ-11, σ-10 and σ01 are obtained to be (0.002 ± 0.001) ×10-18cm2, (1.580 ± 0.034) ×10-18cm2 and (0.648 ± 0.014) ×10-18cm2, respectively. The presently given cross-sections are newly available experimental results for an incident H- energy below 200 MeV and they are also shown to be consistent with recently proposed energy (1 /β2) scaled cross-sections calculated from the previously measured data at 200 and 800 MeV. The present results have a great importance not only at J-PARC for the upgraded H- beam energy of 400 MeV but also for many new and upgrading similar accelerators, where H- beam energies in most cases are considered to be lower than 200 MeV.

  20. Total and differential cross sections of the reaction p + d -> 3He + eta at 48.8 MeV and 59.8MeV excess energy

    CERN Document Server

    Adlarson, P; Bardan, W; Bashkanov, M; Bergmann, F S; Berłowski, M; Bhatt, H; Büscher, M; Calén, H; Ciepał, I; Clement, H; Coderre, D; Czerwiński, E; Demmich, K; Doroshkevich, E; Engels, R; Erven, A; Erven, W; Eyrich, W; Fedorets, P; Föhl, K; Fransson, K; Goldenbaum, F; Goslawski, P; Goswami, A; Grigoryev, K; Gullström, C --O; Hauenstein, F; Heijkenskjöld, L; Hejny, V; Hodana, M; Höistad, B; Hüsken, N; Jany, A; Jany, B R; Jarczyk, L; Johansson, T; Kamys, B; Kemmerling, G; Khan, F A; Khoukaz, A; Kirillov, D A; Kistryn, S; Kłos, B; Kleines, H; Krapp, M; Krzemień, W; Kulessa, P; Kupść, A; Lalwani, K; Lersch, D; Lorentz, B; Magiera, A; Maier, R; Marciniewski, P; Mariański, B; Mikirtychiants, M; Morsch, H --P; Moskal, P; Ohm, H; Ozerianska, I; Passfeld, A; del Rio, E Perez; Piskunov, N M; Podkopał, P; Prasuhn, D; Pricking, A; Pszczel, D; Pysz, K; Pyszniak, A; Redmer, C F; Ritman, J; Roy, A; Rudy, Z; Sawant, S; Schadmand, S; Sefzick, T; Serdyuk, V; Siudak, R; Skorodko, T; Skurzok, M; Smyrski, J; Sopov, V; Stassen, R; Stepaniak, J; Stephan, E; Sterzenbach, G; Stockhorst, H; Ströher, H; Szczurek, A; Täschner, A; Trzciński, A; Varma, R; Wagner, G J; Węglorz, W; Wolke, M; Wrońska, A; Wüstner, P; Wurm, P; Yamamoto, A; Yurev, L; Zabierowski, J; Zieliński, M J; Zink, A; Złomańczuk, J; Żuprański, P; Żurek, M

    2014-01-01

    We present new data for the cross section ratio of the p + d -> 3He + eta reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum J\\"ulich) using a proton beam and a deuterium pellet target. By using an ANKE data point at 59.4 MeV excess energy, an absolute normalization was performed and total and differential cross sections have been determined. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval.

  1. Neutron-induced fission cross sections of 233U and 243Am in the energy range 0.5 Mev En 20 MeV @ n_TOF

    CERN Document Server

    Belloni, F; Milazzo, P M; Calviani, M; Colonna, N; Mastinu, P; Abbondanno, U; Aerts, G; Álvarez, H; Álvarez-Velarde, F; Andriamonje, S; Andrzejewski, J; Assimakopoulos, P; Audouin, L; Badurek, G; Baumann, P; Becvár, F; Berthoumieux, E; Calviño, F; Cano-Ott, D; Capote, R; Carrapiço, C; Cennini, P; Chepel, V; Chiaveri, E; Cortes, G; Couture, A; Cox, J; Dahlfors, M; David, S; Dillmann, I; Domingo-Pardo, C; Dridi, W; Duran, I; Eleftheriadis, C; Embid-Segura, M; Ferrant, L; Ferrari, A; Ferreira-Marques, R; Fujii, K; Furman, W; Goncalves, I; González-Romero, E; Gramegna, F; Guerrero, C; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Igashira, M; Jericha, E; Käppeler, F; Kadi, Y; Karadimos, D; Karamanis, D; Kerveno, M; Koehler, P; Kossionides, E; Krticka, M; Lampoudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martínez, T; Massimi, C; Mengoni, A; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O'Brien, S; Pancin, J; Papachristodoulou, C; Papadopoulos, C; Paradela, C; Patronis, N; Pavlik, A; Pavlopoulos, P; Perrot, L; Pigni, M T; Plag, R; Plompen, A; Plukis, A; Poch, A; Praena, J; Pretel, C; Quesada, J; Rauscher, T; Reifarth, R; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Santos, C; Sarchiapone, L; Savvidis, I; Stephan, C; Tagliente, G; Tain, J L; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vazl, P; Ventura, A; Villamarin, D; Vincente, M C; Vlachoudis, V; Vlastou, R; Voss, F; Walter, S; Wiescher, M; Wisshak, K

    2011-01-01

    Neutron-induced fission cross-sections of actinides have been recently measured at the neutron time of flight facility n_TOF at CERN in the frame of a research project involving isotopes relevant for nuclear astrophysics and nuclear technologies. Fission fragments are detected by a gas counter with good discrimination between nuclear fission products and background events. Neutron-induced fission cross-sections of 233U and 243Am were determined relative to 235U. The present paper reports the results obtained at neutron energies between 0.5 and 20 MeV.

  2. 10. 23 MeV M1 transition in the /sup 48/Ca(p,p ') /sup 48/Ca/sup / reaction at 319 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Nanda, S.K.; Glashausser, C.; Jones, K.W.; McGill, J.A.; Carey, T.A.; McClelland, J.B.; Moss, J.M.; Seestrom-Morris, S.J.; Comfort, J.R.; Levenson, S.

    1984-02-01

    The cross section, analyzing power, and spin-flip probability have been measured for the M1 transition at 10.23 MeV excitation energy in the /sup 48/Ca(p,p') /sup 48/Ca /sup 48/Ca(p,p') /sup 48/Ca agreement with distorted-wave impulse approximation calculations; about 28% of the pure single particle (..nu..f/sub 7/2/ /sup -1/,f/sub 5/2/)M1 strength is observed. The results serve as a good calibration of results expected in heavy nuclei.

  3. Newly developed semi-empirical formulas for (, ) at 17.9 MeV and (, ) at 22.3 MeV reaction cross-sections

    Indian Academy of Sciences (India)

    Eyyup Tel; Abdullah Aydin; E Gamze Aydin; Abdullah Kaplan; Ömer Yavaş; İskender A Reyhancan

    2010-06-01

    In this study, we have investigated the asymmetry term effect for the (, ) and (, ) reaction cross-sections and obtained new coefficients for the (, ) and (, ) reaction cross-sections at 17.9 and 22.3 MeV energies. We have suggested semi-empirical formulas including the non-elastic effects of optical model found by fitting two parameters for proton-induced reactions. The coefficients were determined by least-square fitting method. The obtained cross-section formulas with new coefficients have been discussed and compared with the available experimental data.

  4. Fissility of actinide nuclei induced by 60-130 MeV photons; Fissionabilidade de nucleos actnideos induzida por fotons de energia 60-130 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Morcelle, Viviane; Tavares, Odilon A.P

    2004-06-15

    Nuclear fissilities obtained from recent photofission reaction cross section measurements carried out at Saskatchewan Accelerator Laboratory (Saskatoon, Canada) in the energy range 60-130 MeV for {sup 232} Th, {sup 233} U, {sup 235} U, {sup 238} U, and {sup 237} Np nuclei have been analysed in a systematic way. To this aim, a semiempirical approach has been developed based on the quasi-deuteron nuclear photoabsorption model followed by the process of competition between neutron evaporation and fission for the excited nucleus. The study reproduces satisfactorily well the increasing trend of nuclear fissility with parameter Z{sup 2}=A. (author)

  5. Fission of Weakly Prolate 119Sn and Weakly Oblate 209Bi Nuclei Induced by 500 and 672 MeV Negative Pions

    Institute of Scientific and Technical Information of China (English)

    Mukhtar Ahmed Rana; Gul Sher,Shahid Manzoor; M.I.Shahzad

    2011-01-01

    @@ Fission cross-sections of 119Sn and 209Bi induced by negative pions of two energies 500 and 672 MeV were measured using a CR-39 nuclear track detector.Target-detector stacks were exposed to pion beams at the Brookhaven National Laboratory(USA).Measurement results are compared with the corresponding calculations using the computer code CEM95.Agreement between measurements and calculations is fairly good for the 209Bi target nuclei whereas it is poor for 119Sn at both investigated energies of 500 and 672 MeV Fission cross-section results of 119Sn and 209Bi are explained using the equilibrium properties of these nuclides including nuclear electric quadrupole moments which determine the shapes of nuclei.A logarithmic dependence of fission cross-section on Z2/A is observed for the above-mentioned reactions and a critical limit of Z2/A is identified with the value of 30 which divides the curve of of versus Z2/A into two regimes,one with weak dependence and the other with strong dependence.%Fission cross-sections of 119Sn and 20gBi induced by negative pions of two energies 500 and 672 MeV were measured using a CR-39 nuclear track detector. Target-detector stacks were exposed to pion beams at the Brookhaven National Laboratory (USA). Measurement results are compared with the corresponding calculations using the computer code CEM95. Agreement between measurements and calculations is fairly good for the 209Bi target nuclei whereas it is poor for 119Sn at both investigated energies of 500 and 672 MeV. Fission cross-section results of 119Sn and 209Bi are explained using the equilibrium properties of these nuclides including nuclear electric quadrupole moments which determine the shapes of nuclei. A logarithmic dependence of fission cross-section on Z2/A is observed for the above-mentioned reactions and a critical limit of Z2/A is identified with the value of 30 which divides the curve of at versus Z2 /A into two regimes, one with weak dependence and the other with strong

  6. Stopping Power of Al, Cu, Ag, Au, Pb, and U for 5-18-MeV Protons and Deuterons

    DEFF Research Database (Denmark)

    Sørensen, H.; Andersen, Hans Henrik

    1973-01-01

    High energy protons and deuterons of energies between 9 and 18 MeV have been used to extend earlier measurements of the stopping power of Al, Cu, Ag and Au and the stopping powers of Pb and U in the range 5-18 MeV have been determined for the first time. Mean excitation potentials have been...

  7. THE FE-54,FE-56)(N, P) MN-54,MN-56 REACTIONS AT E(N)=97 MEV

    NARCIS (Netherlands)

    RONNQVIST, T; CONDE, H; OLSSON, N; RAMSTROM, E; ZORRO, R; BLOMGREN, J; HAKANSSON, A; RINGBOM, A; TIBELL, G; JONSSON, O; NILSSON, L; RENBERG, PU; VANDERWERF, SY; UNKELBACH, W; BRADY, FP

    1993-01-01

    Double-differential cross sections of the Fe-54,Fe-56(n, p) reactions have been measured at 97 MeV in the angular range 0-30-degrees for excitation energies up to 40 MeV. The spectra have been decomposed into different multipolarities by a technique based on the use of sample angular distributions

  8. Total reaction cross sections for 20-30 MeV pions and the anomaly of pionic atoms

    Science.gov (United States)

    Friedman, E.; Goldring, A.; Johnson, R. R.; Meirav, O.; Vetterli, D.; Weber, P.; Altman, A.

    1991-03-01

    Total reaction cross sections of 20 MeV π- and 30 MeV π+ and π- have been measured for carbon and nickel targets. The experimental results are in very good agreement with calculations based on commonly accepted pion-nucleus potentials but disagree with calculations based on the potentials associated with the so-called pionic atom anomaly.

  9. Single Particle Strengths and Mirror States in $^{15}$N$-^{15}$O below 12.0 MeV

    CERN Document Server

    Mertin, C E; Crisp, A M; Keeley, N; Kemper, K W; Momtyuk, O; Roeder, B T; Volya, A

    2014-01-01

    New $^{14}$N(d,p) angular distribution data were taken at a deuteron bombarding energy of 16 MeV to locate all narrow single particle neutron states up to 15 MeV in excitation. A new shell model calculation is able to reproduce all levels in $^{15}$N up to 11.5 MeV and is used to characterize a narrow single particle level at 11.236 MeV and to provide a map of the single particle strengths. The known levels in $^{15}$N are then used to determine their mirrors in the lesser known nucleus $^{15}$O. The 2s$_{1/2}$ and 1d$_{5/2}$ single particle centroid energies are determined for the $^{15}$N$-^{15}$O mirror pair as: $^{15}$N $(\\text{2s}_{1/2}) = 8.08$ MeV, $^{15}$O $(\\text{2s}_{1/2}) = 7.43$ MeV, $^{15}$N $(\\text{1d}_{5/2}) = 7.97$ MeV, and $^{15}$O $(\\text{1d}_{5/2}) = 7.47$ MeV. These results confirm the degeneracy of these orbits and that the $^{15}$N$-^{15}$O nuclei are where the transition between the $\\text{2s}_{1/2}$ lying below the $\\text{1d}_{5/2}$ to lying above it, takes place. The $\\text{1d}_{3/2}$...

  10. Response of AGATA Segmented HPGe Detectors to Gamma Rays up to 15.1 MeV

    CERN Document Server

    Crespi, F C L; Camera, F; Akkoyun, S; Atac, A; Bazzacco, D; Bellato, M; Benzoni, G; Blasi, N; Bortolato, D; Bottoni, S; Bracco, A; Brambilla, S; Bruyneel, B; Cerutia, S; Ciemala, M; Coelli, S; Eberth, J; Fanin, C; Farnea, E; Gadea, A; Giaz, A; Gottardo, A; Hess, H; Kmiecik, M; Leoni, S; Maj, A; Mengoni, D; Michelagnoli, C; Million, B; Montanari, D; Pellegri, L; Recchia, F; Reiter, P; Riboldi, S; Ur, C A; Vandone, V; Valiente-Dobon, J J; Wieland, O; Wiens, A

    2012-01-01

    The response of AGATA segmented HPGe detectors to gamma rays in the energy range 2-15 MeV was measured. The 15.1 MeV gamma rays were produced using the reaction d(11B,ng)12C at Ebeam = 19.1 MeV, while gamma-rays between 2 to 9 MeV were produced using an Am-Be-Fe radioactive source. The energy resolution and linearity were studied and the energy-to-pulse-height conversion resulted to be linear within 0.05%. Experimental interaction multiplicity distributions are discussed and compared with the results of Geant4 simulations. It is shown that the application of gamma-ray tracking allows a suppression of background radiation following neutron capture by Ge nuclei. Finally the Doppler correction for the 15.1 MeV gamma line, performed using the position information extracted with Pulse-shape Analysis, is discussed.

  11. Displacement cross sections and PKA spectra: tables and applications. [Neutron damage energy cross sections to 20 MeV, primary knockon atom spectra to 15 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Doran, D G; Graves, N J

    1976-12-01

    Damage energy cross sections to 20 MeV are given for aluminum, vanadium, chromium, iron, nickel, copper, zirconium, niobium, molybdenum, tantalum, tungsten, lead, and 18Cr10Ni stainless steel. They are based on ENDF/B-IV nuclear data and the Lindhard energy partition model. Primary knockon atom (PKA) spectra are given for aluminum, iron, niobium, tantalum, and lead for neutron energies up to 15 MeV at approximately one-quarter lethargy intervals. The contributions of various reactions to both the displacement cross sections (taken to be proportional to the damage energy cross sections) and the PKA spectra are presented graphically. Spectral-averaged values of the displacement cross sections are given for several spectra, including approximate maps for the Experimental Breeder Reactor-II (EBR-II) and several positions in the Fast Test Reactor (FTR). Flux values are included to permit estimation of displacement rates. Graphs show integral PKA spectra for the five metals listed above for neutron spectra corresponding to locations in the EBR-II, the High Flux Isotope Reactor (HFIR), and a conceptual fusion reactor (UWMAK-I). Detailed calculations are given only for cases not previously documented. Uncertainty estimates are included.

  12. An analysis of 100 MeV F 8+ ion and 50 MeV Li 3+ ion irradiation effects on silicon NPN rf power transistors

    Science.gov (United States)

    Pushpa, N.; Praveen, K. C.; Gnana Prakash, A. P.; Prabhakara Rao, Y. P.; Tripati, Ambuj; Revannasiddaiah, D.

    2010-08-01

    The dc characteristics exhibited by NPN power transistors are studied systematically before and after irradiation by 100 MeV F 8+ ions and 50 MeV Li 3+ ions in the dose range of 100 krad to 100 Mrad. The transistor parameters such as excess base current (Δ IB= IBpost- IBpre), dc current gain ( hFE), transconductance ( gm), and collector-saturation current ( ICsat) were studied before and after irradiation. The damage factors ( k) for hFE were calculated for ion irradiated transistors using Messenger-Spratt relation. The base current ( IB) was found to increase significantly after ion irradiation and this in turn decreases the hFE of the transistors. The gm decreases significantly after ion irradiation. Moreover, the output characteristics of irradiated devices also show that the collector current ( IC) in the saturation region ( ICsat) decrease with increase in ion dose. The observed change in these characteristics may be due to the ion induced generation-recombination (G-R) centers in emitter-base (E-B) spacer oxide and the ion induced point defects and their complexes in the transistor structure.

  13. Radiation effects on silicon bipolar transistors caused by 3-10 MeV protons and 20-60 MeV bromine ions

    Science.gov (United States)

    Li, Xingji; Geng, Hongbin; Lan, Mujie; Liu, Chaoming; Yang, Dezhuang; He, Shiyu

    2010-03-01

    The current gain degradation in silicon NPN bipolar junction transistors (BJTs) was examined under irradiation with 3-10 MeV protons and 20-60 MeV bromine (Br) ions with various dose levels. To characterize the radiation damage of the NPN BJTs, the ionizing dose D i and displacement dose D d as a function of chip depth in the NPN BJTs were calculated for both the protons and Br ions with different energies. Based on the irradiation testing and calculated results, it is shown that the current gain degradation of NPN BJTs is sensitive to the ratio of D d/( D d+ D i) in the sensitive region given by protons and Br ions. The irradiation particles (protons and Br ions), which give larger D d/( D d+ D i) at a given total dose, would generate more severe damage to the NPN BJTs. The reciprocal of the gain variation as a function of the displacement dose was compared, showing that the Messenger-Spratt equation becomes relevant to describe the experimental data, when the ratio of the D d/( D d+ D i) are larger and the displacement dose are higher than a certain value.

  14. Elastic and inelastic scattering of {sup 14}N ions by {sup 7}Li at 80 MeV (c.m. 26.7 MeV)

    Energy Technology Data Exchange (ETDEWEB)

    Rudchik, A.T.; Herashchenko, O.V.; Rudchik, A.A.; Mezhevych, S.Yu.; Mokhnach, A.V.; Pirnak, V.M.; Ponkratenko, O.A.; Ilyin, A.P.; Uleshchenko, V.V. [Institute for Nuclear Research, Kyiv (Ukraine); Kemper, K.W. [Florida State University, Physics Department, Tallahassee, Florida (United States); Rusek, K. [National Institute for Nuclear Research, Warsaw (Poland); Heavy Ion Laboratory of Warsaw University, Warsaw (Poland); Koshchy, E.I. [Kharkiv National University, Kharkiv (Ukraine); Kliczewski, S.; Siudak, R.; Szczurek, A. [H. Niewodniczanski Institute of Nuclear Physics, Cracow (Poland); Plujko, V.A. [Taras Shevchenko Kyiv National University, Kyiv (Ukraine); Choinski, J. [Heavy Ion Laboratory of Warsaw University, Warsaw (Poland); Stolarz, A. [National Institute for Nuclear Research, Warsaw (Poland)

    2014-10-15

    New angular distribution data for {sup 7}Li + {sup 14}N elastic and inelastic scattering at the energy E{sub lab} ({sup 14}N) = 80 MeV (c.m. 26.7MeV) are presented. The data were analyzed within the optical model and the coupled-reaction-channels method using a channels-coupling scheme that included the {sup 7}Li and {sup 14}N inelastic scattering channels, spin reorientations of {sup 7}Li and {sup 14}N as well as most important transfer reactions. The low-energy excited states of {sup 7}Li and {sup 14}N were assumed to be collective in nature. The {sup 7}Li + {sup 14}N potential parameters as well as deformation parameters of {sup 7}Li and {sup 14}N were deduced. The {sup 7}Li + {sup 14}N potential and the data were compared with those of {sup 6}Li + {sup 14}N to observe isotopic differences. The enhanced large-angle elastic and inelastic scattering data are shown to have a large contribution from the ground-state reorientation of {sup 7}Li. (orig.)

  15. The 13C(n,α0)10Be cross section at 14.3 MeV and 17 MeV neutron energy

    Science.gov (United States)

    Kavrigin, P.; Belloni, F.; Frais-Koelbl, H.; Griesmayer, E.; Plompen, A. J. M.; Schillebeeckx, P.; Weiss, C.

    2017-09-01

    At nuclear fusion reactors, CVD diamond detectors are considered an advantageous solution for neutron flux monitoring. For such applications the knowledge of the cross section of neutron-induced nuclear reactions on natural carbon are of high importance. Especially the (n,α0) reactions, yielding the highest energy reaction products, are of relevance as they can be clearly distinguished in the spectrum. The 13C(n,α0)10Be cross section was measured relative to 12C(n,α0)9Be at the Van de Graaff facility of EC-JRC Geel, Belgium, at 14.3 MeV and 17.0 MeV neutron energies. The measurement was performed with an sCVD (single-crystal Chemical Vapor Deposition) diamond detector, where the detector material acted simultaneously as sample and as sensor. A novel data analysis technique, based on pulse-shape discrimination, allowed an efficient reduction of background events. The results of the measurement are presented and compared to previously published values for this cross-section.

  16. Simulation study of neutron production in thick beryllium targets by 35 MeV and 50.5 MeV proton beams

    Science.gov (United States)

    Shin, Jae Won; Park, Tae-Sun

    2017-09-01

    A data-driven nuclear model dedicated to an accurate description of neutron productions in beryllium targets bombarded by proton beams is developed as a custom development that can be used as an add-on to GEANT4 code. The developed model, G4Data(Endf7.1), takes as inputs the total and differential cross section data of ENDF/B-VII.1 for not only the charge-exchange 9Be(p,n)9B reaction which produces discrete neutrons but also the nuclear reactions relevant for the production of continuum neutrons such as 9Be(p,pn)8Be and 9Be(p,n α) 5Li . In our benchmarking simulations for two experiments with 35 MeV and 50.5 MeV proton beams impinged on 1.16 and 1.05 cm thick beryllium targets, respectively, we find that the G4Data(Endf7.1) model can reproduce both the total amounts and the spectral shapes of the measured neutron yield data in a satisfactory manner, while all the considered hadronic models of GEANT4 cannot.

  17. M-shell electron capture and direct ionization of gold by 25-MeV carbon and 32-MeV oxygen ions

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, M.C.; McDaniel, F.D.; Duggan, J.L.; Miller, P.D.; Pepmiller, P.L.; Krause, H.; Rosseel, T.; Rayburn, L.A.; Mehta, R.; Lapicki, G.

    1984-01-01

    M-shell x-ray production cross sections have been measured for thin solid targets of Au for 25 MeV /sup 12/C/sup q+/ (q = 4, 5, 6) and for 32 MeV /sup 16/O/sup q+/ (q = 5, 7, 8). The microscopic cross sections were determined from measurements made with targets ranging in thickness from 0.5 to 100 ..mu..g/cm/sup 2/. For projectiles with one or two K-shell vacancies, the M-shell x-ray production cross sections are found to be enhanced over those by projectiles without a K-shell vacancy. The sum of direct ionization to the continuum (DI) and electron capture (EC) to the L, M, N ... shells and EC to the K-shell of the projectile have been extracted from the data. The results are compared to the predictions of first Born theories i.e. PWBA for DI and OBK of Nikolaev for EC and the ECPSSR approach that accounts for energy loss, Coulomb deflection and relativistic effects in the perturbed stationary state theory. 25 references, 3 figures, 1 table.

  18. 200 MeV proton radiography studies with a hand phantom using a prototype proton CT scanner.

    Science.gov (United States)

    Plautz, Tia; Bashkirov, V; Feng, V; Hurley, F; Johnson, R P; Leary, C; Macafee, S; Plumb, A; Rykalin, V; Sadrozinski, H F-W; Schubert, K; Schulte, R; Schultze, B; Steinberg, D; Witt, M; Zatserklyaniy, A

    2014-04-01

    Proton radiography has applications in patient alignment and verification procedures for proton beam radiation therapy. In this paper, we report an experiment which used 200 MeV protons to generate proton energy-loss and scattering radiographs of a hand phantom. The experiment used the first-generation proton computed tomography (CT) scanner prototype, which was installed on the research beam line of the clinical proton synchrotron at Loma Linda University Medical Center. It was found that while both radiographs displayed anatomical details of the hand phantom, the energy-loss radiograph had a noticeably higher resolution. Nonetheless, scattering radiography may yield more contrast between soft and bone tissue than energy-loss radiography, however, this requires further study. This study contributes to the optimization of the performance of the next-generation of clinical proton CT scanners. Furthermore, it demonstrates the potential of proton imaging (proton radiography and CT), which is now within reach of becoming available as a new, potentially low-dose medical imaging modality.

  19. Proton computed tomography images with algebraic reconstruction

    Science.gov (United States)

    Bruzzi, M.; Civinini, C.; Scaringella, M.; Bonanno, D.; Brianzi, M.; Carpinelli, M.; Cirrone, G. A. P.; Cuttone, G.; Presti, D. Lo; Maccioni, G.; Pallotta, S.; Randazzo, N.; Romano, F.; Sipala, V.; Talamonti, C.; Vanzi, E.

    2017-02-01

    A prototype of proton Computed Tomography (pCT) system for hadron-therapy has been manufactured and tested in a 175 MeV proton beam with a non-homogeneous phantom designed to simulate high-contrast material. BI-SART reconstruction algorithms have been implemented with GPU parallelism, taking into account of most likely paths of protons in matter. Reconstructed tomography images with density resolutions r.m.s. down to 1% and spatial resolutions CT in hadron-therapy.

  20. Isolation and Identification of Pathogenic Mink Enteritis Virus MEV-ZJ1 Strain%致病性水貂肠炎病毒MEV-ZJ1株的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    谭斌; 陈微晶; 武华

    2011-01-01

    自临床疑似水貂病毒性肠炎发病貂的粪便中分离出1株病毒,经病毒形态观察、理化特性检测、血清学、聚合酶链式反应(PCR)和动物试验鉴定表明,该分离毒为水貂肠炎病毒(mink enteritis virus,MEV),命名为MEV-ZJ1株.用分离毒接种水貂,试验动物均表现出典型水貂病毒性肠炎临床症状.研究表明,MEV-ZJ1分离株对水貂具有致病性,是1株强毒,为进一步开展该病毒流行病学、致病机理、疫苗免疫与诊断检测的研究奠定了基础.%A virus strain was isolated from feces of a mink suspected MEV infection. It was demonstrated to be MEV by morphology, physical and chemical properties, serum test, PCR and animal test,and it was named MEV-ZJ1. Minks were artificially infected by MEV-ZJ1 developed obvious symptoms of enteritis post-inoculation. The MEV-ZJ1 strain was virulent for minks. The successful isolation of MEV-ZJ1 provided a basis for further search on epidemiology, pathogenesis, vaccination and diagnostic.

  1. Designing of the 14 MeV neutron moderator for BNCT

    Institute of Scientific and Technical Information of China (English)

    CHENG Dao-Wen; LU Jing-Bin; YANG Dong; LIU Yu-Min; WANG Hui-Dong; MA Ke-Yan

    2012-01-01

    In boron neutron capture therapy (BNCT),the ratio of the fast neutron flux to the neutron flux in the tumor (RFNT) must be less than 3%.If a D-T neutron generator is used in BNCT,the 14 MeV neutron moderator must be optimized to reduce the RFNT.Based on the neutron moderation theory and the simulation results,tungsten,lead and diamond were used to moderate the 14 MeV neutrons.Satisfying RFNT of less than 3%,the maximum neutron flux in the tumor was achieved with a three-layer moderator comprised of a 3 cm thick tungsten layer,a 14 cm thick lead layer and a 21 cm thick diamond layer.

  2. Design and Construction of the 3.2 Mev High Voltage Column for Darht II

    CERN Document Server

    Peters, C; Yu, S; Eylon, S; Henestroza, E

    2000-01-01

    A 3.2 MeV injector has been designed and built for the Darht II Project at Los Alamos Lab. The installation of the complete injector system is nearing completion at this time. The requirements for the injector are to produce a 3.2 MeV, 2000 ampere electron pulse with a flattop width of at least 2-microseconds and emittance of less than 0.15 p cm-rad normalized. A large high voltage column has been built and installed. The column is vertically oriented, is 4.4 meters long, 1.2 meters in diameter, and weights 5700 kilograms. A novel method of construction has been employed which utilizes bonded mycalex insulating rings. This paper will describe the design, construction, and testing completed during construction. Mechanical aspects of the design will be emphasized.

  3. Structural damage in InGaN induced by MeV heavy ion irradiation

    Science.gov (United States)

    Zhang, L. M.; Fadanelli, R. C.; Hu, P.; Zhao, J. T.; Wang, T. S.; Zhang, C. H.

    2015-08-01

    In0.18Ga0.82N films were irradiated with 4 MeV 84Kr and 8.9 MeV 209Bi ions to various fluences at room temperature. The irradiated films were analyzed by means of Rutherford backscattering/channeling (RBS/C) and high resolution X-ray diffraction (HRXRD). The RBS/C measurements show that under the irradiation conditions, the relative lattice disorder in the films, obtained from the normalized backscattering yield, exhibits a rapid increase in the range from ∼2% to 68%. There is also an increasing lattice expansion of the films with increasing ion fluence, as determined by the HRXRD measurements. At a comparable level of lattice disorder, the Kr irradiation leads to a more pronounced lattice expansion than the Bi irradiation. This may be attributed to a larger portion of the single interstitials in the films produced by the lighter Kr ion irradiation.

  4. Photoluminescence study of 1018 meV defect lines from ion-implanted silicon

    CERN Document Server

    Lee, H S; Seong, E Z; Kim, S M; Lim, H J

    1999-01-01

    We investigated the defects of ion-implanted silicon with boron and argon ions using photoluminescence method. The 1018 meV line, so called I sub 1 line, and its phonon side bands were observed in both boron- and argon-implanted silicon crystals. In argon-implanted silicon crystals, we observed 1009 meV line (I sub r - Ar) and its phonon side bands which arose from argon-I sub 1 complex in addition to the splitting of the I sub 1 line. Annealing temperature dependence of the intensities of the I sub 1 and I sub 1 -Ar lines in argon-implanted silicon was very similar for both Czochralski and float zone silicon crystals whereas that of boron-implanted silicon was very different between the two growing methods. We discussed on the origin of the defects responsible for the I sub 1 and I sub 1 - Ar lines.

  5. Cross sections from 800 MeV proton irradiation of terbium

    Energy Technology Data Exchange (ETDEWEB)

    Engle, J.W., E-mail: jwengle@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mashnik, S.G.; Bach, H.; Couture, A.; Jackman, K.; Gritzo, R.; Ballard, B.D.; Fassbender, M.; Smith, D.M.; Bitteker, L.J.; Ullmann, J.L.; Gulley, M.S.; Pillai, C.; John, K.D.; Birnbaum, E.R. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Nortier, F.M., E-mail: meiring@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-11-02

    Terbium foils were irradiated with 800 MeV protons to ascertain the potential for production of lanthanide isotopes of interest in medical, astrophysical, and basic science research and to contribute to nuclear data repositories. Isotopes produced in the foil were quantified by gamma spectroscopy. Cross sections for 35 isotopes produced in the irradiation are reported and compared with predictions by the MCNP6 transport code using the CEM03.03, Bertini and INCL + ABLA event generators. Our results indicate the need to accurately consider fission and fragmentation of relatively light target nuclei like terbium in the modeling of nuclear reactions at 800 MeV. The predictive power of the code was found to be different for each event generator tested but was satisfactory for most of the product yields in the mass region where spallation reactions dominate. However, none of the event generators' results are in complete agreement with measured data.

  6. A novel way of constraining WIMPs annihilations in the Sun: MeV neutrinos

    CERN Document Server

    Bernal, Nicolas; Palomares-Ruiz, Sergio

    2012-01-01

    Annihilation of dark matter particles accumulated in the Sun would produce a flux of high-energy neutrinos whose prospects of detection in neutrino telescopes and detectors have been extensively discussed in the literature. However, for many channels into Standard Model particles, there would also be a flux of neutrinos in the MeV range from the decays at rest of muons and positively charged pions. These low-energy neutrinos have never been considered before and they open the possibility to also constrain dark matter annihilation in the Sun into e+e-, mu+mu- or light quarks. Here we perform a detailed analysis using the recent Super-Kamiokande data in the few tens of MeV range to set limits on the WIMP-nucleon scattering cross section for different annihilation channels.

  7. The optimization for the conceptual design of a 300 MeV proton synchrotron

    CERN Document Server

    An, Yuwen; Wang, Sheng; Huang, Liangsheng

    2016-01-01

    A research complex for aerospace radiation effects research has been proposed in Harbin Institute of Technology. Its core part is a proton accelerator complex, which consists of a 10 MeV injector, a 300 MeV synchrotron and beam transport lines. The proton beam extracted from the synchrotron is utilized for the radiation effects research. Based on the conceptual design [1], the design study for optimizing the synchrotron has been done. A new lattice design was worked out, and the multi-turn injection and slow extraction system were optimized with the new lattice design. In order to improve the time structure of the extracted beam, a RF knock-out method is employed. To meet the requirement of accurate control of dose, the frequency of the RF kicker is well investigated.

  8. Polarization transfer for inclusive proton-nucleus inelastic scattering at 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Fergerson, R.; McGill, J.; Glashausser, C.; Jones, K.; Nanda, S.; Sun Zuxun; Barlett, M.; Hoffmann, G.; Marshall, J.; McClelland, J.; and others

    1988-11-01

    The polarization-transfer observables D/sub N//sub N/, D/sub S//sub S/, D/sub L//sub L/, D/sub L//sub S/, and D/sub S//sub L/ have been measured at 800 MeV for polarized proton inelastic scattering from /sup 1/H, /sup 2/H, and /sup 12/C with energy losses up to about 400 MeV. The scattering angles in the laboratory were 5/sup 0/, 11/sup 0/, and 20/sup 0/. No large differences between the observables for the three targets were seen. The data for /sup 12/C in the quasielastic region are reasonably well explained by nonrelativistic and relativistic models of one-step quasifree scattering. Specifically nuclear effects appear small in both the quasielastic and delta regions.

  9. Beam characteristics of a new generation 50 MeV racetrack microtron.

    Science.gov (United States)

    Masterson, M E; Chui, C S; Febo, R; Hung, J D; Fuks, Z; Mohan, R; Ling, C C; Kutcher, G J; Bjork, S; Enstrom, J

    1995-06-01

    The first of a new generation of microtron accelerators has been installed and tested. It is currently in use for multisegment conformal radiotherapy at our institution. The unit produces x rays and electrons from 10 to 50 MeV in 5 MeV increments. It incorporates a 64 leaf, doubly focused multileaf collimator (MLC), which can be used to shape x-ray and electron beams. Both x-ray and electron beams are produced by magnetically scanning the electron beams from the accelerator. The new generation unit incorporates a purging magnet to sweep away any primary or secondary electrons that pass through the target(s). In this paper, the beam characteristics of the accelerator that were studied during acceptance testing are described. Representative examples of depth doses, beam profiles, output factors, and elementary beam distributions are presented and discussed, in comparison with the earlier generation of microtron accelerators and with other radiotherapy machines.

  10. Transverse Beam Emittance Measurements of a 16 MeV Linac at the Idaho Accelerator Center

    Energy Technology Data Exchange (ETDEWEB)

    S. Setiniyaz, T.A. Forest, K. Chouffani, Y. Kim, A. Freyberger

    2012-07-01

    A beam emittance measurement of the 16 MeV S-band High Repetition Rate Linac (HRRL) was performed at Idaho State University's Idaho Accelerator Center (IAC). The HRRL linac structure was upgraded beyond the capabilities of a typical medical linac so it can achieve a repetition rate of 1 kHz. Measurements of the HRRL transverse beam emittance are underway that will be used to optimize the production of positrons using HRRL's intense electron beam on a tungsten converter. In this paper, we describe a beam imaging system using on an OTR screen and a digital CCD camera, a MATLAB tool to extract beamsize and emittance, detailed measurement procedures, and the measured transverse emittances for an arbitrary beam energy of 15 MeV.

  11. Modification and alignment of beam line of 10 MeV RF electron beam accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Barnwal, R; Ghodke, S R; Bhattacharjee, D; Kumar, M; Jayaprakash, D; Chindarkar, A R; Mishra, R L; Kumar, M; P, Dixit K; S, Acharya; Barje, S R; Lawangare, N K; C, Saroj P; Nimje, V T; Chandan, S; Tillu, A R; V, Sharma; Chavan, R B [Accelerator and Pulse Power Division, BARC, Mumbai, India-400085 (India); Dolas, S [Centre for Design and Manufacturing, BARC, Mumbai, India-400085 (India); Kulkarni, S Y [SAMEER, IIT Powai campus, Mumbai, India-400076 (India)], E-mail: rajesh_barc47@indiatimes.com (and others)

    2008-05-01

    A 10 MeV, 10 kW RF industrial Electron linac designed and developed at BARC is installed at the Electron Beam Center Kharghar, Navi Mumbai. The entire RF accelerator assembly consists of Electron gun, RF source, RF linac structure, Beam diagnostic chamber, Drift tube, Scanning magnet, Beam sensing aperture, Scan horn, and is spread over two floors at EBC. The paper discusses in detail about the alignment procedure adopted for the equipments of 10 MeV RF beamline. The complete electron beamline will be maintained under ultra high vacuum of the order of 10-7 torr. The paper discusses about the present problem of alignment, measurement technique of alignment, reason for misalignment, possible ways to solve the problem, equipment used for alignment, supports and arrestors, verification of alignment under vacuum.

  12. Modification & alignment of beam line of 10 MeV RF electron beam accelerator

    Science.gov (United States)

    Barnwal, R.; Ghodke, S. R.; Bhattacharjee, D.; Kumar, M.; Jayaprakash, D.; Chindarkar, A. R.; Mishra, R. L.; Dolas, S.; Kulkarni, S. Y.; Kumar, M.; P, Dixit K.; S, Acharya; Barje, S. R.; Lawangare, N. K.; C, Saroj P.; Nimje, V. T.; Chandan, S.; Tillu, A. R.; V, Sharma; Chavan, R. B.; V, Yadav; P, Roychowdhury; Mittal, K. C.; Chakravarthy, D. P.; Ray, A. K.

    2008-05-01

    A 10 MeV, 10 kW RF industrial Electron linac designed and developed at BARC is installed at the Electron Beam Center Kharghar, Navi Mumbai. The entire RF accelerator assembly consists of Electron gun, RF source, RF linac structure, Beam diagnostic chamber, Drift tube, Scanning magnet, Beam sensing aperture, Scan horn, and is spread over two floors at EBC. The paper discusses in detail about the alignment procedure adopted for the equipments of 10 MeV RF beamline. The complete electron beamline will be maintained under ultra high vacuum of the order of 10-7 torr. The paper discusses about the present problem of alignment, measurement technique of alignment, reason for misalignment, possible ways to solve the problem, equipment used for alignment, supports & arrestors, verification of alignment under vacuum

  13. A 7MeV S-Band 2998MHz Variable Pulse Length Linear Accelerator System

    CERN Document Server

    Hernandez, Michael; Mishin, Andrey V; Saverskiy, Aleksandr J; Skowbo, Dave; Smith, Richard

    2005-01-01

    American Science and Engineering High Energy Systems Division (AS&E HESD) has designed and commissioned a variable pulse length 7 MeV electron accelerator system. The system is capable of delivering a 7 MeV electron beam with a pulse length of 10 nS FWHM and a peak current of 1 ampere. The system can also produce electron pulses with lengths of 20, 50, 100, 200, 400 nS and 3 uS FWHM with corresponding lower peak currents. The accelerator system consists of a gridded electron gun, focusing coil, an electrostatic deflector system, Helmholtz coils, a standing wave side coupled S-band linac, a 2.6 MW peak power magnetron, an RF circulator, a fast toroid, vacuum system and a PLC/PC control system. The system has been operated at repetition rates up to 250pps. The design, simulations and experimental results from the accelerator system are presented in this paper.

  14. Commissioning of a 6 MeV X-Band SW Accelerating Guide

    CERN Document Server

    Jin, Q; Sun, X; Tao, X; Tong, D

    2004-01-01

    A 6 MeV, X-band on-axis SW electron linear accelerating guide is being developed in Accelerator laboratory of Tsinghua University. It can be suitable for portable radiation therapy and radiography. The design, manufacture and high power test of the guide are given in this paper. The guide is 38 cm long and contains 25 accelerating cells with 24 coupling cells, operated in the π/2 mode. The RF power source is a pulsed magnetron at 9300 MHz with 1.5 MW peak power. The results of beam tests are following: the electron energy is more than 6 MeV at 50 mA and focal spot size is less than φ 1.5 mm without any focusing solenoid.

  15. Modification of ROSPEC to cover neutrons from thermal to 18 MeV.

    Science.gov (United States)

    Ing, H; Djeffal, S; Clifford, T; Li, L; Noulty, R; Machrafi, R

    2007-01-01

    Rotating Spectrometer (ROSPEC) is a neutron spectrometer designed to measure neutron energy distributions, and provide accurate neutron dosimetry. It is a completely self-contained unit and measures neutron energy via recoiling protons in gas proportional counters. Each of the four original gas counters is dedicated to a particular neutron energy range dictated by sensitivity to gamma rays at the low energy end of the spectrum and by proton collisions with the counter walls at the high energy end. Introduced originally in 1992, ROSPEC has a proven operational record with a program of continued upgrades. The operating range of the original ROSPEC spans 50 keV-4.5 MeV. The range of the ROSPEC has now been extended down to include epithermal and thermal neutrons by adding two 2 in. (3)He counters. Also, an optional simple scintillation spectrometer was designed to extend the upper limit of ROSPEC up to 18 MeV.

  16. Variation Tendency of the Align Network for the 100MeV Proton Linac

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Daeil; Kwon, Hyeokjung; Kim, Hansung; Seo, Donghyuk; Cho, Yongsub [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, the variation tendency of the align networks is checked and the survey results are considered to compensate the position of the accelerator components in the tunnel. Two years ago, the align networks on the tunnel were installed and checked to align the accelerator components. In recent survey of align networks, the displacement by temperature was confirmed according to comparison of the position. When the accelerator components are realigned, the displacement should be used to compensate position of the accelerator components. 100MeV proton linac for KOMAC (Korea Multi-purpose Accelerator Complex) has been operated at the Gyeong-ju. Linac is composed of a 50keV proton injector, a 3MeV RFQ, DTL tanks and a beam dump. The align networks were built to align the accelerator components. The survey work of align networks should be accomplished whenever need the alignment of the accelerator by using the laser tracker.

  17. Ion beam induced luminescence from diamond using an MeV ion microprobe

    Energy Technology Data Exchange (ETDEWEB)

    Bettiol, A.A.; Jamieson, D. N.; Prawer, S.; Allen, M.G. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1993-12-31

    Analysis of the luminescence induced by a MeV ion beam offers the potential to provide useful information about the chemical properties of atoms in crystals to complement the information provided by more traditional Ion Beam Analysis (IBA) such as Rutherford Backscattering Spectrometry (RBS), ion channeling and Particle Induced X-ray Emission (PIXE). Furthermore, the large penetration depth of the MeV ion beam offers several advantages over the relatively shallow penetration of keV electrons typically employed in cathodoluminescence. An Ion Beam Induced Luminescence (IBIL) detection system was developed for the Melbourne microprobe that allows the spatial mapping of the luminescence signal along with the signals from RBS and PIXE. Homoepitaxial diamond growth has been studied and remarkable shifts in the characteristic blue luminescence of diamond towards the green were observed in the overgrowth. This has been tentatively identified as being due to transition metal inclusions in the epitaxial layers. 8 refs., 2 refs.

  18. Analysing powers and spin correlations in deuteron-proton charge exchange at 726 MeV

    CERN Document Server

    Dymov, S; Bagdasarian, Z; Barsov, S; Carbonell, J; Chiladze, D; Engels, R; Gebel, R; Grigoryev, K; Hartmann, M; Kacharava, A; Khoukaz, A; Komarov, V; Kulessa, P; Kulikov, A; Kurbatov, V; Lomidze, N; Lorentz, B; Macharashvili, G; Mchedlishvili, D; Merzliakov, S; Mielke, M; Mikirtychyants, M; Mikirtychyants, S; Nioradze, M; Ohm, H; Prasuhn, D; Rathmann, F; Serdyuk, V; Seyfarth, H; Shmakova, V; Ströher, H; Tabidze, M; Trusov, S; Tsirkov, D; Uzikov, Yu; Valdau, Yu; Weidemann, C; Wilkin, C

    2015-01-01

    The charge exchange of vector polarised deuterons on a polarised hydrogen target has been studied in a high statistics experiment at the COSY-ANKE facility at a deuteron beam energy of Td = 726 MeV. By selecting two fast protons at low relative energy E_{pp}, the measured analysing powers and spin correlations are sensitive to interference terms between specific neutron-proton charge-exchange amplitudes at a neutron kinetic energy of Tn ~ 1/2 Td =363 MeV. An impulse approximation calculation, which takes into account corrections due to the angular distribution in the diproton, describes reasonably the dependence of the data on both E_{pp} and the momentum transfer. This lends broad support to the current neutron-proton partial-wave solution that was used in the estimation.

  19. The LENS 7 MeV, 10 mA Proton Linac

    CERN Document Server

    Derenchuk, Vladimir Peter; Bogdanov, Alexander; Jones, William P; Rinckel, Thomas; Solberg, Keith

    2005-01-01

    The Indiana University Cyclotron Facility (IUCF) has constructed and placed in operation a Low Energy Neutron Source (LENS) using a 10 mA, 7 MeV proton beam incident on a beryllium target. The proton delivery system (PDS) consists of a 25 keV proton injector, an AccSys Technology, Inc. PL7 Linac* and a beam transport line with non-linear beam spreading.** The accelerator and beamline equipment used in this construction are refurbished and upgraded components from the IUCF CIS/Cooler synchrotron*** facility. After commissioning the beam current at 7 MeV will be 10 mA with a pulse width of up to 300 μs and > 1% duty factor. The PDS was constructed and commissioning started in 2004. First operating results will be described.

  20. Cross Sections from 800 MeV Proton Irradiation of Terbium

    CERN Document Server

    Engle, J W; Bach, H; Couture, A; Jackman, K; Gritzo, R; Ballard, B D; Faßbender, M; Smith, D M; Bitteker, L J; Ullmann, J L; Gulley, M; Pillai, C; John, K D; Birnbaum, E R; Nortier, F M

    2012-01-01

    A single terbium foil was irradiated with 800 MeV protons to ascertain the potential for production of lanthanide isotopes of interest in medical, astrophysical, and basic science research and to contribute to nuclear data repositories. Isotopes produced in the foil were quantified by gamma spectroscopy. Cross sections for 36 isotopes produced in the irradiation are reported and compared with predictions by the MCNP6 transport code using the CEM03.03, Bertini, and INCL+ABLA event generators. Our results indicate the need to accurately consider fission and fragmentation of relatively light target nuclei like terbium in the modeling of nuclear reactions at 800 MeV. The predictive power of the code was found to be different for each event generator tested but was satisfactory for most of the product yields in the mass region where spallation reactions dominate. However, none of the event generators' results are in complete agreement with measured data.

  1. Measurements of the neutron activation cross sections for Bi and Co at 386 MeV.

    Science.gov (United States)

    Yashima, H; Sekimoto, S; Ninomiya, K; Kasamatsu, Y; Shima, T; Takahashi, N; Shinohara, A; Matsumura, H; Satoh, D; Iwamoto, Y; Hagiwara, M; Nishiizumi, K; Caffee, M W; Shibata, S

    2014-10-01

    Neutron activation cross sections for Bi and Co at 386 MeV were measured by activation method. A quasi-monoenergetic neutron beam was produced using the (7)Li(p,n) reaction. The energy spectrum of these neutrons has a high-energy peak (386 MeV) and a low-energy tail. Two neutron beams, 0° and 25° from the proton beam axis, were used for sample irradiation, enabling a correction for the contribution of the low-energy neutrons. The neutron-induced activation cross sections were estimated by subtracting the reaction rates of irradiated samples for 25° irradiation from those of 0° irradiation. The measured cross sections were compared with the findings of other studies, evaluated in relation to nuclear data files and the calculated data by Particle and Heavy Ion Transport code System code.

  2. The New Sorgentina Fusion Source-NSFS: 14 MeV neutrons for fusion and beyond

    Science.gov (United States)

    Pietropaolo, A.; Console Camprini, P.; Agostini, P.; Amendola, R.; Angelone, M.; Bernardi, D.; Bruni, F.; Capogni, M.; Colognesi, D.; Faccini, R.; Filabozzi, A.; Flammini, D.; Fiori, F.; Frisoni, M.; Grazzi, F.; Pillon, M.; Pizzuto, A.; Quintieri, L.; Sacchetti, F.; Valente, P.

    2016-09-01

    The importance of the design for the realization of an intense 14 MeV neutron facility devoted to test and validate materials suitable for harsh neutron environments, such as a fusion reactor, is well established. The “New Sorgentina” Fusion Source (NSFS) is a project that proposes an intense D-T 14 MeV neutron source achievable with T and D ion beams impinging on 2 m radius rotating targets. NSFS may produce about 1015 n/s at the target and has to be intended as an European facility that maybe realized in a few years, once provided a preliminary technological program devoted to the operation of the ion source in continuous mode, target heat loading/removal, target and tritium handling, inventor as well as site licensing. In this contribution, the main characteristics of NSFS project will be presented and its possible use as a multipurpose facility outlined.

  3. The X(3872) and the 3941 MeV peak in omega+J/Psi

    CERN Document Server

    Bugg, D V

    2004-01-01

    Belle data for the pi-pi mass spectrum in X(3872) -> pi\\pi + JPsi are well fitted by rho + J/\\Psi with JPC = 1++, but are poorly fitted by the pi-pi S-wave. Formulae for partial wave amplitudes are given for all likely JPC and decay modes of the 3941 MeV peak in omega + J/Psi. Angular correlations involving up to five angles may allow a spin-parity determination, even with quite low statistics. Special attention is given to the case where X(3872) is a cusp or quasi-bound state with the same quantum numbers as the 3941 MeV peak.

  4. Reaction cross sections for protons in the energy range 220-570 MeV

    CERN Document Server

    Renberg, P U; Measday, D F; Pepin, M; Serre, Claude; Schwaller, P

    1972-01-01

    Proton reaction cross sections have been measured for targets of natural isotopic abundance of the following elements and compounds: He, Be, C, Al, Fe, Cu, Ge, Sn, Pb, H/sub 2/O, B/sub 4/C and NaI. Data for proton energies between 220 and 570 MeV have been obtained with two types of transmission-counter assembly. The total errors are of the order of +or-3%. A slight increase of the reaction cross sections with energy is observed for most of the elements studied. The results interpreted in terms of the semi-classical theory of reaction cross section as function of energy clearly demonstrate the onset of pion- production above 250 MeV. (32 refs).

  5. Measurement of neutron-induced fission cross-sections of Th232, U238, U233 and Np237 relative to U235 from 1 MeV to 200 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Shcherbakov, O.A.; Laptev, A.B.; Petrov, G.A. [Petersburg Nuclear Physics Inst., Gatchina, Leningrad district (Russian Federation); Fomichev, A.V.; Donets, A.Y.; Osetrov, O.I.

    1998-11-01

    The measurements of neutron-induced cross-section ratios for Th232, U238, U233 and Np237 relative to U235 have been carried out in the energy range from 1 MeV up to 200 MeV using the neutron time-of-flight spectrometer GNEIS based on 1 GeV proton synchrocyclotron. Below 20 MeV, the results of present measurements are roughly in agreement with evaluated data though there are some discrepances to be resolved. (author)

  6. Phenomenological Study of 3He Photodisintegration up to 150 MeV

    Institute of Scientific and Technical Information of China (English)

    WANG Cheng-Bin; ZHU Zhi-Yuan

    2008-01-01

    @@ A parametrization of 3He(γ,p)2H cross section data at laboratory photon energies between 9 and 150MeV is carried out with a simple phenomenological function. The differential cross section data are normalized to the total cross-section values, which are consistent with the measurement from monochromatic photon beams. The obtained results give a good representation of the experimental points.

  7. Scattering of {sup 8}He on {sup 208}Pb at 22 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Marquinez-Duran, G.; Sanchez-Benitez, A. M.; Martel, I.; Berjillos, R.; Duenas, J. A.; Parkar, V. V. [Depto. de Fisica Aplicada, Universidad de Huelva, 21071 Huelva (Spain); Acosta, L. [Depto. de Fisica Aplicada, Universidad de Huelva, 21071 Huelva, Spain and Laboratori Nazionali del Sud, INFN, Via Santa Sofia 62, 95123, Catania (Italy); Rusek, K. [Heavy Ion Laboratory, University of Warsaw (Poland); Alvarez, M. A. G.; Gomez-Camacho, J. [Centro Nacional de Aceleradores, 41092, Sevilla, Spain and Depto. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Borge, M. J. G.; Cruz, C.; Cubero, M.; Pesudo, V.; Tengblad, O. [Instituto de Estructura de la Materia, CSIC, 28006 Madrid (Spain); Chbihi, A. [GANIL, CEA and IN2P3-CNRS, B.P. 5027, 14076 Caen cedex (France); Fernandez-Garcia, J. P.; Moro, A. M. [Depto. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Fernandez-Martinez, B.; Labrador, J. A. [Centro Nacional de Aceleradores, 41092, Sevilla (Spain); and others

    2013-06-10

    The skin nucleus {sup 8}He is investigated by measuring the angular distribution of the elasticly scattered {sup 8}He and the {sup 6,4}He fragments produced in the collision with a {sup 208}Pb target at 22 MeV, just above the Coulomb barrier. The experiment was carried out at SPIRAL/GANIL in 2010. Here we present preliminary results for the elastic scattering.

  8. 19. 7 MeV resonance in the system /sup 16/O + /sup 12/C

    Energy Technology Data Exchange (ETDEWEB)

    Wilschut, H.W.; Braun-Munzinger, P.; Berkowitz, G.M.; Freifelder, R.H.; Karp, J.S.; Renner, T.R. (State Univ. of New York, Stony Brook (USA). Dept. of Physics)

    1982-06-10

    The 19.7 MeV structure in the system /sup 12/C + /sup 16/O is investigated by measuring angular distributions and excitation functions for elastic and inelastic scattering with very high resolution. From a quasi phase shift analysis, it is deduced that the structure is a true resonance with Jsup(..pi..) = 14/sup +/. The deduced small elastic partial width indicates that the structure of this state is intermediate between a molecular and a compound nuclear state.

  9. Shielding studies for 2.5 MeV neutrons using GEANT4

    Science.gov (United States)

    Tovar, Felipe; Castro-Colin, Miguel; Sajo-Bohus, Laszlo

    2008-10-01

    By means of the software GEANT4, a toolkit based on the Monte Carlo method, we seek to study the dispersive effects that 2.5 MeV neutrons have, as well the gamma-yield, after interacting with various attenuating materials with simple geometrical configurations. A simulated mass of Uranium-238 is considered in the study with the purpose of observing the behavior of its characteristic yield after fast neutron irradiation.

  10. THE ORIGIN OF THE COSMIC GAMMA-RAY BACKGROUND IN THE MeV RANGE

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Lapuente, Pilar [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, c/. Serrano 121, E-28006, Madrid (Spain); The, Lih-Sin; Hartmann, Dieter H.; Ajello, Marco [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States); Canal, Ramon [Institut de Ciències del Cosmos (UB-IEEC), c/. Martí i Franqués 1, E-08028, Barcelona (Spain); Röpke, Friedrich K.; Ohlmann, Sebastian T. [Institute of Theoretical Physics and Astrophysics, University of Würzburg, D-97074, Würzburg (Germany); Hillebrandt, Wolfgang [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching bei München (Germany)

    2016-04-01

    There has been much debate about the origin of the diffuse γ-ray background in the MeV range. At lower energies, AGNs and Seyfert galaxies can explain the background, but not above ≃0.3 MeV. Beyond ∼10 MeV blazars appear to account for the flux observed. That leaves an unexplained gap for which different candidates have been proposed, including annihilations of WIMPS. One candidate is Type Ia supernovae (SNe Ia). Early studies concluded that they were able to account for the γ-ray background in the gap, while later work attributed a significantly lower contribution to them. All those estimates were based on SN Ia explosion models that did not reflect the full 3D hydrodynamics of SN Ia explosions. In addition, new measurements obtained since 2010 have provided new, direct estimates of high-z SN Ia rates beyond z ∼ 2. We take into account these new advances to see the predicted contribution to the gamma-ray background. We use here a wide variety of explosion models and a plethora of new measurements of SN Ia rates. SNe Ia still fall short of the observed background. Only for a fit, which would imply ∼150% systematic error in detecting SN Ia events, do the theoretical predictions approach the observed fluxes. This fit is, however, at odds at the highest redshifts with recent SN Ia rate estimates. Other astrophysical sources such as flat-spectrum radio quasars do match the observed flux levels in the MeV regime, while SNe Ia make up to 30%–50% of the observed flux.

  11. Biomedical user facility at the 400-MeV Linac at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Chu, W.T.

    1993-12-01

    In this paper, general requirements are discussed on a biomedical user facility at the Fermilab`s 400-MeV Linac, which meets the needs of biology and biophysics experiments, and a conceptual design and typical operations requirements of the facility is presented. It is assumed that no human patient treatment will take place in this facility. If human patients were treated, much greater attention would have to be paid to safeguarding the patients.

  12. Proton-deuteron breakup cross sections in collinear geometry at 28. 6 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Birchall, J.; Svenne, J.P.; de Jong, M.S.; McKee, J.S.C.; Ramsay, W.D.; Al-Ghazi, M.S.A.L.; Videla, N.

    1979-10-01

    Deuteron breakup cross sections induced by 28.6 MeV protons have been measured in collinear and noncollinear geometry and the results compared with an exact three-body calculation using the Doleschall code. This calculation includes two-body interactions in S and P waves and, in addition, a tensor force. The agreement with experiment in all cases is excellent. No evidence is seen for a collinearity enhancement.

  13. The measurement of KNN and KLL in at 800 MeV

    Science.gov (United States)

    Glass, G.; Bhatia, T. S.; Hiebert, J. C.; Northcliffe, L. C.; Tippens, W. B.; Verwest, B. J.; Hollas, C. L.; Newsom, C. R.; Ransome, R. D.; Riley, P. J.; Pepin, G. P.; Bonner, B. E.; Simmons, J. E.

    1983-09-01

    The spin-transfer parameters KNN and KLL have been measured for ? at 0° and 800 MeV for neutron momenta between 700 and {1200 MeV}/{c}. Peak values of KNN and KLL are -0.30 ± 0.05 and -0.5 ± 0.1 respectively. These results are in substantial disagreement with VerWest's field theoretic model.

  14. Isotopic Production Cross Sections in Proton-Nucleus Collisions at 200 MeV

    CERN Document Server

    Machner, H; Baruth-Ram, K; Carter, J; Cowley, A A; Goldenbaum, F; Nangu, B M; Pilcher, J V; Sellschop, J P Friedel; Sideras-Haddad, E; Smit, F D; Spoelstra, B; Steyn, D

    2006-01-01

    Intermediate mass fragments (IMF) from the interaction of $^{27}$Al, $^{59}$Co and $^{197}$Au with 200 MeV protons were measured in an angular range from 20 degree to 120 degree in the laboratory system. The fragments, ranging from isotopes of helium up to isotopes of carbon, were isotopically resolved. Double differential cross sections, energy differential cross sections and total cross sections were extracted.

  15. Large-angle. pi. /sup +/p elastic scattering at 66. 8 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Brack, J.T.; Kraushaar, J.J.; Rilett, D.J.; Ristinen, R.A.; Ottewell, D.F.; Smith, G.R.; Jeppesen, R.G.; Stevenson, N.R.

    1988-11-01

    Pion-proton elastic scattering measurements at six angles from 101/sup 0/ to 147/sup 0/ center of mass at 66.8 MeV verify previously published differential cross sections which are at variance with earlier data of others and with generally accepted phase-shift solutions which incorporate these earlier data. The present single-arm measurements were made with solid targets and an array of scintillation counters which measured the time of flight of scattered pions.

  16. Nuclear multifragmentation by 700–1500 MeV photons: New data of GRAAL experiment

    Energy Technology Data Exchange (ETDEWEB)

    Nedorezov, V. G., E-mail: vladimir@cpc.inr.ac.ru; Lapik, A. M. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation); Collaboration: GRAAL Collaboration

    2015-12-15

    The cross sections of carbon nucleus photodisintegration into protons and neutrons with high multiplicity for photon energies from 700 to 1500 MeV were measured. The experiment was performed at the tagged photon beam of the GRAAL setup using the wide-aperture detector LAGRANγE. It was shown that multifragmentation up to complete disintegration into separate nucleons is initiated by elementary reactions of meson photoproduction with a subsequent intranuclear cascade.

  17. Study of the narrow structure at 1685 MeV in γp→ηp

    Energy Technology Data Exchange (ETDEWEB)

    Anisovich, A.V. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Helmholtz-Institut fur Strahlen- u. Kernphysik, Universität Bonn (Germany); Klempt, E. [Helmholtz-Institut fur Strahlen- u. Kernphysik, Universität Bonn (Germany); Kuznetsov, V. [Institute for Nuclear Research, 117312 Moscow (Russian Federation); Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Nikonov, V.A. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Helmholtz-Institut fur Strahlen- u. Kernphysik, Universität Bonn (Germany); Polyakov, M.V., E-mail: maxim.polyakov@tp2.rub.de [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Sarantsev, A.V., E-mail: andsar@hiskp.uni-bonn.de [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300 (Russian Federation); Helmholtz-Institut fur Strahlen- u. Kernphysik, Universität Bonn (Germany); Thoma, U. [Helmholtz-Institut fur Strahlen- u. Kernphysik, Universität Bonn (Germany)

    2013-02-12

    Results of a coupled channel isobar analysis of new high-statistics data on γp→pη from MAMI are presented. A fit using known broad resonances and only standard background amplitudes cannot describe the relatively narrow peaking structure in the cross section in the mass region of 1660–1750 MeV which follows a minimum. An improved description of the data can be reached by either assuming the existence of a narrow resonance at a mass of about 1700 MeV with small photo-coupling or by a threshold effect. In the latter case the observed structure is explained by a strong (resonant or non-resonant) γp→ωp coupling in the S{sub 11} partial wave. When the beam asymmetry data, published by part of the GRAAL Collaboration, are included in the fit, the solution with a narrow P{sub 11} state is slightly preferred. In that fit, mass and width of the hypothetical resonance are determined to M∼1694 MeV and Γ∼40 MeV, respectively, and the photo-coupling to √(Br{sub ηN})A{sub 1/2}{sup p}∼2.6⋅10{sup −3} GeV{sup −1/2}. High-precision measurements of the target asymmetry and F-observable are mandatory to establish the possible existence of such a narrow state and to provide the necessary information to define which partial wave is responsible for the structure observed in the data.

  18. Pulsed 5 MeV standing wave electron linac for radiation processing

    Science.gov (United States)

    Auditore, L.; Barnà, R. C.; de Pasquale, D.; Italiano, A.; Trifirò, A.; Trimarchi, M.

    2004-03-01

    Several modern applications of radiation processing require compact and self-contained electron accelerators. To match these requirements, a 5MeV, 1kW electron linac has been developed at the Dipartimento di Fisica (Università di Messina) and will be described in this paper. This standing wave accelerator, driven by a 3GHz, 2.5MW magnetron generator, has an autofocusing structure and will be used to study several applications of radiation processing.

  19. Measurement of Neutron Transmission for Tungsten With 2.8 MeV Neutrons

    Institute of Scientific and Technical Information of China (English)

    REN; Jie; RUAN; Xi-chao; BAO; Jie; NIE; Yang-bo; ZHOU; Zu-ying

    2012-01-01

    <正>The neutron transmission for different thickness of tungsten plates for 2.8 MeV neutrons was measured with TOF technique using the d-D reaction neutron source at the 600 kV Cococroft-Walton accelerator at CIAE. The sensitivity for distinguishing the thickness of the tungsten plate was determined with this method. The tungsten plate was put at the beam direction and 1.7 m from the neutron source, and

  20. Pion-Nucleus potentials in the energy range of 0-80 MeV

    Science.gov (United States)

    Meirav, O.; Friedman, E.; Altman, A.; Hannah, M.; Johnson, R. R.; Gill, D. R.

    1987-12-01

    Data for the elastic scattering of 30-80 MeV positive and negative pions by a wide range of nuclei is analysed with an Ericson-Ericson MSU type optical potential. By use of consistent sets of data for π+ and π- and of experimental results for total reaction cross sections we obtain for the first time optical potentials that describe well all the data without the need of introducing non-standard charge-dependent effects.

  1. Polarization observables for the reaction pp -> pp. pi. /sup 0/ at 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Riley, P.J.; Bachman, M.; Hollas, C.L.; McNaughton, K.H.; Xu Shenwu; Bonner, B.E.; Van Dyck, O.B.; McGill, J.; McNaughton, M.W.; Peng, J.C.

    1987-10-22

    The Wolfenstein polarization observables D/sub NN/, D/sub S..cap omega../ and D/sub L..cap omega../, where ..cap omega.. denotes a mixture of S and L polarization components, the induced polarization P, and the analysing power A have been measured for the reaction pp -> pp..pi../sup 0/ at 800, 733, and 647 MeV. Comparisons are made to theoretical predictions of the model of Dubach, Kloet and Silbar.

  2. The viable motheaten (mev) mouse--a new model for arthritis.

    Science.gov (United States)

    Kovarik, J; Kuntz, L; Ryffel, B; Borel, J F

    1994-10-01

    Homozygous mev mice are first identified at the age of 3-4 days by focal depigmentation of the skin, followed by patchy absence of hair and by necrotic lesions on paws, tail and ears. Of particular interest are the inflammatory reactions in the paws of these animals which consist mainly of polymorphonuclear and mononuclear cell infiltration in the subcutaneous tissue extending to the periosteum and joint, resulting in focal destructive arthritis and osteomylitis. These lesions are to some extent reminiscent of an acute form of rheumatoid-like arthritis. Since mev mice are sterile, a limited number of symptomatic offspring can be obtained by cross-breeding their heterozygous siblings which are phenotypically not distinguishable from mice lacking this mutation. In order to produce a sufficient number of diseased animals for performing pharmacological studies, we have established a model by transferring this disease in lethally irradiated, 8- to 10-week-old syngeneic mice which were grafted with mev spleen cells. Such reconstituted recipients develop first inflammatory symptoms of the paws 2 to 3 weeks after cell transfer. The arthritic inflammation finally affects all paws and toes by 30 to 50 days. This procedure increased the number of mev-like mice expressing arthritis, allowing assessment of the effects of standard reference drugs used in the therapy of rheumatoid arthritis (RA). The immunosuppressants cyclosporin and rapamycin and the steroid dexamethasone at therapeutic concentrations exert a strong inhibitory effect on the development of arthritis in this novel model. In contrast, the non-steroidal anti-inflammatory drug phenylbutazone shows only a moderate effect. These results indicate the particular sensitivity of this model for efficacy of potentially new therapeutic but non-cytostatic compounds for clinical use.

  3. Radiation Damage of F8 Lead Glass with 20 MeV Electrons

    CERN Document Server

    Schaefer, B D; McChesney, P; Shepherd, M R; Frye, J M

    2011-01-01

    Using a 20 MeV linear accelerator, we investigate the effects of electromagnetic radiation on the optical transparency of F8 lead glass. Specifically, we measure the change in attenuation length as a function of radiation dose. Comparing our results to similar work that utilized a proton beam, we conclude that F8 lead glass is more susceptible to proton damage than electron damage.

  4. Radiation damage of F8 lead glass with 20 MeV electrons

    Science.gov (United States)

    Schaefer, B. D.; Mitchell, R. E.; McChesney, P.; Shepherd, M. R.; Frye, J. M.

    2012-03-01

    Using a 20 MeV linear accelerator, we investigate the effects of electromagnetic radiation on the optical transparency of F8 lead glass. Specifically, we measure the change in attenuation length as a function of radiation dose. Comparing our results to similar work that utilized a proton beam, we conclude that F8 lead glass is more susceptible to proton damage than electron damage.

  5. Nucleon structure with pion mass down to 149 MeV

    CERN Document Server

    Green, Jeremy; Krieg, Stefan; Negele, John; Pochinsky, Andrew; Syritsyn, Sergey

    2012-01-01

    We present isovector nucleon observables: the axial, tensor, and scalar charges and the Dirac radius. Using the BMW clover-improved Wilson action and pion masses as low as 149 MeV, we achieve good control over chiral extrapolation to the physical point. Our analysis is done using three different source-sink separations in order to identify excited-state effects, and we make use of the summation method to reduce their size.

  6. Analyzing power in n vector+d elastic scattering at 67 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Ruehl, H.; Dechant, B.; Krug, J.; Luebcke, W.; Spangardt, G.; Steinke, M.; Stephan, M.; Kamke, D. (Bochum Univ. (Germany, F.R.). Inst. fuer Experimentalphysik 1); Balewski, J.; Bodek, K.; Jarczyk, L.; Strzalkowski, A. (Uniwersytet Jagiellonski, Krakow (Poland). Inst. Fizyki); Hajdas, W.; Kistryn, S.; Mueller, R.; Lang, J. (Eidgenoessische Technische Hochschule, Zurich (Switzerland). Inst. fuer Mittelenergiephysik); Henneck, R. (Basel Univ. (Switzerland). Inst. fuer Physik); Witala, H.; Cornelius, T.; Gloeckle, W. (Bochum Univ. (Germany, F.R.). Inst. fuer Theoretische Physik 2)

    1991-03-18

    The analyzing power A{sub y} of {sup 2}H(n vector, n){sup 2}H elastic scattering at E{sub n}=67 MeV has been measured in the angular range 30deg<{theta}{sub c.m.}<165deg. The data are in good agreement with the results of our rigorous three-nucleon calculations employing the PARIS and the BONN B potential. (orig.).

  7. Impurity/defect interactions during MeV Si{sup +} ion implantation annealing

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, A.; Koveshnikov, S.; Christensen, K. [North Carolina State Univ., Raleigh, NC (United States)] [and others

    1995-08-01

    Ion implantation of dopant atoms at MeV energies is currently being explored in several integrated circuit device manufacturing processes. MeV implantation offers immediate advantages such as vertical well modulation, latch-up protection, device structure isolation, and reduced temperature processing. Simultaneously, it presents an opportunity to achieve {open_quotes}proximity{close_quotes} gettering of impurities from the active device region by placing high impurity solubility and/or secondary defect gettering sites within microns of the surface. If the MeV implanted species is a dopant ion, all three gettering mechanisms, i.e, segregation, relaxation and injection, can be involved in the gettering process, complicating the analysis and optimization of the process. However, investigation of gettering using non-dopant Si{sup +} ion damage allows the relaxation component of the gettering process to be isolated and examined separately. In general, gettering is verified by a reduction in impurity concentration in the region of interest, usually the device region, and/or a build-up of concentration/precipitation in a non-device sink region. An alternate and more meaningful approach is to use simple devices as materials characterization probes via changes in the electrical activity of the gettering sites. Device space charge probes also allow the evolution of the defect sites upon contamination to be tracked. We report here results of the electrical, structural, and chemical characterization of MeV implanted Si{sup +} damage using Deep Level Transient Spectroscopy (DLTS), Transmission Electron Microscopy (TEM), and Secondary Ion Mass Spectroscopy (SIMS). The damage has been characterized both as a function of annealing from 600 to 1100{degrees}C for 1 hr, and after contamination with Fe followed by low temperature gettering annealing.

  8. Installation and Test of 100 MeV Cyclotron Safety Interlock System

    Institute of Scientific and Technical Information of China (English)

    HOU; Shi-gang; SONG; Guo-fang; LI; Zhen-guo; WANG; Feng; LV; Yin-long; XING; Jian-sheng; CAI; Hong-ru; YIN; Zhi-guo; WU; Long-cheng; XIE; Huai-dong; GE; Tao; CAO; Lei; FU; Xiao-liang; WEN; Li-peng

    2013-01-01

    The safety system is an important part of BRIF project,which will play a key role for protection of staff,and equipments.100 MeV cyclotron will deliver proton beam of 200μA with energy of 100 MeV.Radiation caused by beam loss will be occurred when the machine running or commissioning,which is hazard to staff and device,so a set of interlock system is designed for protecting people and apparatus.

  9. Cavity Formation in Aluminium Irradiated with a Pulsating Beam of 225 MeV Electrons

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Bilde-Sørensen, Jørgen; Leffers, Torben

    1984-01-01

    High-purity aluminium was irradiated with a pulsating beam of 225 MeV electrons to a maximum dose of 0.035 dpa with a helium generation rate of up to 17 appm/dpa. The irradiated samples contained cavities in the size range 5 to 70 nm. In a zone of up to 14 μm from the grain boundaries cavity size...

  10. R&D of the Fluoroscopes of 100 MeV Cyclotron Beam Lines

    Institute of Scientific and Technical Information of China (English)

    YIN; Meng; GUAN; Feng-ping; XIE; Huai-dong; ZHENG; Xia; XING; Jian-sheng; LV; Yin-long

    2013-01-01

    Beijing Radioactive Ion-beam Facility(BRIF)consists of a 100 MeV H-cyclotron CYCIAE-100and nine beam lines.All the beam lines provide the channels of the proton beam or the neutron beam to the terminal of physics experiment.There are many beam diagnosis monitors distributing along the beam lines,including,Faraday cups,beam position monitors,fluoroscopes,collimators,emittance measurement

  11. Using the transportable, computer-operated, liquid-scintillator fast-neutron spectrometer system

    Energy Technology Data Exchange (ETDEWEB)

    Thorngate, J.H.

    1988-11-01

    When a detailed energy spectrum is needed for radiation-protection measurements from approximately 1 MeV up to several tens of MeV, organic-liquid scintillators make good neutron spectrometers. However, such a spectrometer requires a sophisticated electronics system and a computer to reduce the spectrum from the recorded data. Recently, we added a Nuclear Instrument Module (NIM) multichannel analyzer and a lap-top computer to the NIM electronics we have used for several years. The result is a transportable fast-neutron spectrometer system. The computer was programmed to guide the user through setting up the system, calibrating the spectrometer, measuring the spectrum, and reducing the data. Measurements can be made over three energy ranges, 0.6--2 MeV, 1.1--8 MeV, or 1.6--16 MeV, with the spectrum presented in 0.1-MeV increments. Results can be stored on a disk, presented in a table, and shown in graphical form. 5 refs., 51 figs.

  12. Preliminary Design of 3.5-MeV Helium RFQ for Fusion Materials Radiation Damage Study

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yongsub; Jang, Jiho; Kwon, Hyeokjung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    This work briefly summarized a 3.5 MeV helium RFQ design for alpha irradiation study. We have studied a 3.5-MeV helium RFQ for the fusion material damage study, especially for the alpha particle effects produced by DT reaction. The total length is about 3.7 m, which is compact to be installed in a general experiment hall with a reasonable radiation shielding. For the ion source of He, we are considering a microwave ion source. KOMAC (KOrea Multi-purpose Accelerator Complex) has developed a 100-MeV proton linac which includes a 50-keV ion source, a 3-MeV RFQ (Radio Frequency Quadrupole), and a 100-MeV DTL (drift tube linac). The RFQ technology can be also used to MeV ion beam applications. Especially helium beam with the kinetic energy of 3.5 MeV can be used to study the alpha particle irradiation from DT nuclear fusion reaction on the first wall of the fusion reactor.

  13. X-ray observations of MeV electron precipitation with a balloon-borne germanium spectrometer

    Science.gov (United States)

    Millan, R. M.; Lin, R. P.; Smith, D. M.; Lorentzen, K. R.; McCarthy, M. P.

    2002-12-01

    The high-resolution germanium detector aboard the MAXIS (MeV Auroral X-ray Imaging and Spectroscopy) balloon payload detected nine X-ray bursts with significant flux extending above 0.5 MeV during an 18 day flight over Antarctica. These minutes-to-hours-long events are characterized by an extremely flat spectrum (~E-2) similar to the first MeV event discovered in 1996, indicating that the bulk of parent precipitating electrons is at relativistic energies. The MeV bursts were detected between magnetic latitudes 58°-68° (L-values of 3.8-6.7) but only in the late afternoon/dusk sectors (14:30-00:00 MLT), suggesting scattering by EMIC (electromagnetic ion cyclotron) waves as a precipitation mechanism. We estimate the average flux of precipitating E >= 0.5 MeV electrons to be ~360 cm-2s-1, corresponding to about 5 × 1025 such electrons precipitated during the eight days at L = 3.8-6.7, compared to ~2 × 1025 trapped 0.5-3.6 MeV electrons estimated from dosimeter measurements on a GPS spacecraft. These observations show that MeV electron precipitation events are a primary loss mechanism for outer zone relativistic electrons.

  14. Simulations of Beam Quality in a 13 MeV PET Cyclotron

    Directory of Open Access Journals (Sweden)

    A. Pramudita

    2015-12-01

    Full Text Available Simulation of the trajectories of negative hydrogen ion (H− beam in a 13 MeV PET cyclotron (DECY-13 were carried out by using the Runge-Kutta (RK4 approximation method and Scilab 5.4.1. The magnetic and electric fields were calculated using Opera-3d/TOSCA softwares at 1 mm resolution. The cyclotron is of a fourth-harmonics type, meaning that the acceleration occurs four times per cycle, with a radiofrequency (RF field of 77.66 MHz frequency and 40 kV amplitude. The calculations and simulations show that the maximum distance between the ion source and the puller is about 6 mm, while the maximum width of the beam at 13 MeV is about 10 mm, and the initial phase between the RF field and the beam ranges from -10° to 10°, with a yield of about 10% of the beam from the ion source getting accelerated to 13 MeV.

  15. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Katayama, Tadashi; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1993-10-01

    In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (J.P.N.).

  16. Comprehensive Measurement of Neutron Yield Produced by 62 MeV Protons on Beryllium Target

    CERN Document Server

    Osipenko, M; Alba, R; Ricco, G; Schillaci, M; Barbagallo, M; Boccaccio, P; Celentano, A; Colonna, N; Cosentino, L; Del Zoppo, A; Di Pietro, A; Esposito, J; Figuera, P; Finocchiaro, P; Kostyukov, A; Maiolino, C; Santonocito, D; Scuderi, V; Viberti, C M

    2013-01-01

    A low-power prototype of neutron amplifier, based on a 70 MeV, high current proton cyclotron being installed at LNL for the SPES RIB facility, was recently proposed within INFN-E project. This prototype uses a thick Beryllium converter to produce a fast neutron spectrum feeding a sub-critical reactor core. To complete the design of such facility the new measurement of neutron yield from a thick Beryllium target was performed at LNS. This measurement used liquid scintillator detectors to identify produced neutrons by Pulse Shape Discrimination and Time of Flight technique to measure neutron energy in the range 0.5-62 MeV. To extend the covered neutron energy range He3 detector was used to measure neutrons below 0.5 MeV. The obtained yields were normalized to the charge deposited by the proton beam on the metallic Beryllium target. These techniques allowed to achieve a wide angular coverage from 0 to 150 degrees and to explore almost complete neutron energy interval.

  17. MeV Argon ion beam generation with narrow energy spread

    CERN Document Server

    Xu, Jiancai; Shen, Baifei; Zhang, Hui; Li, Shun; Yu, Yong; Li, Jinfeng; Lu, Xiaoming; Wang, Cheng; Wang, Xinliang; Liang, Xiaoyan; Leng, Yuxin; Li, Ruxin; Xu, Zhizhan

    2016-01-01

    Laser driven particle acceleration has shown remarkable progresses in generating multi-GeV electron bunches and 10s of MeV ion beams based on high-power laser facilities. Intense laser pulse offers the acceleration field of 1012 Volt per meter, several orders of magnitude larger than that in conventional accelerators, enabling compact devices. Here we report that a highly-collimated argon ion beam with narrow energy spread is produced by irradiating a 45-fs fully-relativistic laser pulse onto an argon cluster target. The highly-charged (Argon ion with charge state of 16+) heavy ion beam has a minimum absolute energy spread of 0.19 MeV per nucleon at the energy peak of 0.39 MeV per nucleon. we identify a novel scheme from particle-in-cell simulations that greatly reduces the beam energy spread. The laser-driven intense plasma wakefield has a strong modulation on the ion beam in a way that the low energy part is cut off. The pre-accelerated argon ion beam from Coulomb explosion thus becomes more mono-energetic ...

  18. Simulation of Electron Behavior in PIG Ion Source for 9MeV Cyclotron

    CERN Document Server

    Ghergherehchi, Mitra; Yeon, Yeong- Heum; Chai, Jong- Seo

    2013-01-01

    In this paper, we focus on a PIG source for producing intense H-ions inside a 9MeV cyclotron. The properties of the PIG ion source were simulated for a variety of electric field distributions and magnetic field strengths using CST Particle Studio. After analyzing secondary electron emission (SEE) as a function of both magnetic and electric field strengths, we found that for the modeled PIG geometry a magnetic field strength of 0.2 T provided the best results in term of number of secondary electrons. Furthermore, at 0.2 T the number of secondary electrons proved to be greatest regardless of the cathode potential. Also the modified PIG ion source with quartz insulation tubes was tested in KIRAMS-13 cyclotron by varying gas flow rate and arc current, respectively. The capacity of the designed ion source was also demonstrated by producing plasma inside the constructed 9MeV cyclotron. As a result, the ion source is verified to be capable to produce intense H- beam and high ion beam current for the desired 9 MeV cy...

  19. Temperature and 8 MeV electron irradiation effects on GaAs solar cells

    Indian Academy of Sciences (India)

    Asha Rao; Sheeja Krishnan; Ganesh Sajeev; K Siddappa

    2010-06-01

    GaAs solar cells hold the record for the highest single band-gap cell efficiency. Successful application of these cells in advanced space-borne systems demand characterization of cell properties like dark current under different ambient conditions and the stability of the cells against particle irradiation in space. In this paper, the results of the studies carried out on the effect of 8 MeV electron irradiation on the electrical properties of GaAs solar cells are presented. The – (current–voltage) characteristics of the cells under dark and AM1.5 illumination condition are studied and 8 MeV electron irradiation was carried out on the cells where they were exposed to graded doses of electrons from 1 to 100 kGy. The devices were also characterized using capacitance measurements at various frequencies before and after irradiation. The effect of electron irradiation on the solar cell parameters was studied. It is found that only small changes were observed in the GaAs solar cell parameters up to an electron dose of 100 kGy, exhibiting good tolerance for electrons of 8 MeV energy.

  20. Design study of a 9 MeV compact cyclotron system for PET

    Science.gov (United States)

    Lee, Byeong-No; Shin, Seung-Wook; Song, Hoseung; Kim, Hyun-Wook; Chai, Jong-Seo

    2013-06-01

    A cyclotron is an accelerator which can be applied to both cancer diagnosis and treatment. Among commercially sold cyclotrons, the major energy is used for positron emission tomography (PET) ranges from 10 to 20 MeV. In this research, 9 MeV compact cyclotron for PET was designed. The research was conducted on the response cross section and the yield for the energy distribution to decide the design features. Also, it was determined the specifications on the basis of the fluoro-deoxy-glucose (FDG) maximum dose. The machine, which has a 20 uA beam current, is designed to be installed in small-to-medium-sized hospitals in local cities because of its relatively light weight (6 tons). This compact cyclotron, which provides 9-MeV proton beams, is composed of a azimuthally varying field (AVF) electromagnet, 83-MHz RF systems with a 20 kW amplifier, a panning ion gauge (PIG) type ion-source for negative hydrogen, and a double-stage high-vacuum system. The basic model design was done by using 3-D CAD program, CATIA and all the field calculations were performed using commercial electromagnetic field analysis code, OPERA-3D TOSCA. From this research, we expect a time reduction for FDG production, a decrease of radioactive exposure for workers, and an equipment cost reduction.

  1. Release the beams! - Linac4 ready to hit the 50 MeV mark

    CERN Multimedia

    Katarina Anthony

    2015-01-01

    The Linac4 accelerator is now prepared to reach 50 MeV. This milestone energy - expected in the coming weeks - will allow the machine to act as a replacement for the ageing Linac2, four years before it takes over at the head of the accelerator chain in 2020.    Inside the Linac4 tunnel, the final DTL cavities will guide beams to 50 MeV.  (Image: Stephan Russenschuck.) The Linac4 accelerator will bring H- ion beams (hydrogen atoms with an extra electron) up to 160 MeV for injection into the PS Booster. As a key part of the LHC injector upgrade programme, Linac4 will allow the PS Booster to double its beam brightness, which will contribute to increasing the LHC’s luminosity. Linac4 will soon bring beams up to 50 MeV - the current energy delivered by the Linac2 accelerator. This milestone follows on from another recent accomplishment: the installation and commissioning of the final Drift Tube Linac (DTL) tank. Using an innovati...

  2. EXPERIMENTAL ANALYSES OF SPALLATION NEUTRONS GENERATED BY 100 MEV PROTONS AT THE KYOTO UNIVERSITY CRITICAL ASSEMBLY

    Directory of Open Access Journals (Sweden)

    CHEOL HO PYEON

    2013-02-01

    Full Text Available Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS facility at the Kyoto University Critical Assembly (KUCA. High-energy protons (100 MeV obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

  3. New applications of 10 MeV electrons for reeled goods

    Science.gov (United States)

    Günthard, C.; Lee, D. W.

    2000-03-01

    Because of their high penetration capability, electron beams produced by 10 MeV machines are increasingly used for the sterilization processing of medical devices. Worldwide there are already more than 20 such machines in action for this purpose. But compared with electron beam sterilization, the physical crosslinking of plastic products with 10 MeV has not been as much investigated as in the range of low and medium energy. So the products with high wall thickness or big dimensions are still chemically crosslinked as the penetration and power of the beam of existing accelerators was not sufficient for those products. But now radiation crosslinking is possible also for higher dimensions of reeled goods due to higher beam power up to 150 kW, and one machine with different handling systems can be used for sterilization and modification of plastic products. The aim of our work is to examine the homogeneous crosslinking of industrial products by a 10 MeV/150 kW electron beam as for instance for XLPE-c pipes and heat shrinkable tubes. Furthermore the uniformity of crosslinking especially along the roundness is measured, which is one of the essential quality characteristics.

  4. Ion desorption from frozen H 2O irradiated by MeV heavy ions

    Science.gov (United States)

    Collado, V. M.; Farenzena, L. S.; Ponciano, C. R.; Silveira, E. F. da; Wien, K.

    2004-10-01

    Nitrogen (0.13-0.85 MeV) and 252Cf fission fragments (˜65 MeV) beams are employed to sputter positive and negative secondary ions from frozen water. Desorption yields are measured for different ice temperatures and projectile energies. Target surface is continuously refreshed by condensed water while the target temperature varies and ice thickness changes. In both projectile energy ranges, the preferentially ejected ions are H +, H2+ and (H 2O) nH +-cluster ions. The yields of the corresponding negative ions H - and (H 2O) nO - or (H 2O) nOH - are 1-2 orders of magnitude lower. The (H 2O) nH + desorption yields decrease exponentially as the cluster size, n, increases. In the low energy range, the desorption of positive ion clusters may occur in a two-step process: first, desorption of preformed H 2O clusters and, then, ionization by H + or H 3O + capture. For 0.81 MeV N + projectile ions, the cluster ion emission contributes with 0.05% to the total H 2O desorbed yield. There are indications that emission of the (H 2O) nH + disappears for an electronic energy loss lower than 20 eV/Å. For the high energy range, desorption of small ion clusters is particularly enhanced, revealing that a fragmentation process also exists.

  5. Measurement of 15 MeV gamma-rays with the Ge cluster detectors of EUROBALL

    CERN Document Server

    Million, B; Camera, F; Brambilla, S; Gadea, A; Giugni, D; Herskind, B; Kmiecik, M; Isocrate, R; Leoni, S; Maj, A; Prelz, F; Wieland, O

    2000-01-01

    A measurement of the response to 15.1 MeV gamma-rays has been made for the Ge cluster detectors in the EUROBALL array. Each cluster detector consists of seven germanium capsules surrounded by a single anticompton shield of BGO. The reaction D( sup 1 sup 1 B,gamma) sup 1 sup 2 C+n at E sub b sub e sub a sub m =19.1 MeV has been employed. The 'adding-back' of signals simultaneously present in the capsules composing each cluster detector has been made on an event by event basis. The intensity in full-energy peak increases by a factor of three as compared to that of the spectrum obtained by summing the individual spectra of the 7 capsules. The pulse height to energy conversion is found to be very linear from few hundreds keV to 15 MeV. The efficiency is discussed relative to that of large volume BaF sub 2 scintillators.

  6. High-quality beam generation using an RF gun and a 150 MeV microtron

    Science.gov (United States)

    Kuroda, R.; Washio, M.; Kashiwagi, S.; Kobuki, T.; Ben-Zvi, I.; Wang, X. J.; Hori, T.; Sakai, F.; Tsunemi, A.; Urakawa, J.; Hirose, T.

    2000-11-01

    Low-emittance sub-picosecond electron pulses are expected to be used in a wide field, such as free electron laser, laser acceleration, femtosecond X-ray generation by Inverse Compton scattering, pulse radiolysis, etc. In order to produce the low-emittance sub-picosecond electron pulse, we are developing a compact Racetrack Microtron (RTM) with a new 5 MeV injection system adopting a laser photo cathode RF gun (Washio et al., Seventh China-Japan Bilateral Symposium on Radiation Chemistry, October 28, Cengdu, China, 1996). The operation of RTM has been kept under a steady state of beam loading for long pulse mode so far (Washio et al., J. Surf. Sci. Soc. Jpn. 19 (2) (1998) 23). In earlier work (Washio et al., PAC99, March 31, New York, USA, 1999), we have succeeded in the numerical simulation for the case of single short pulse acceleration. Finally, the modified RTM was demonstrated as a useful accelerator for a picosecond electron pulse generation under a transient state of beam loading. In the simulation, a picosecond electron pulse was accelerated to 149.6 MeV in RTM for the injection of 5 MeV electron bunch with a pulse length of 10 ps (FWHM), a charge of 1 nC per pulse, and an emittance of 3 πmm mrad.

  7. Bremsstrahlung component of the diffuse galactic gamma-ray emission at MeV energies

    Energy Technology Data Exchange (ETDEWEB)

    Sacher, W.; Schoenfelder, V.

    1984-04-15

    Recently the galactic plane has been resolved at low and medium ..gamma..-ray energies in the directions toward the center and anticenter. Spectral measurements are now available at those energies, where the contribution of ..pi../sup 0/-decay from nuclear reactions of cosmic-ray protons (and heavier nuclei) with interstellar matter can be neglected. Under the assumption that most of the observed ..gamma..-ray flux below 30 MeV is produced by electron bremsstrahlung, restrictions on the energy spectrum of cosmic-ray electrons in interstellar space below 100 MeV are derived. The most accurate bremsstrahlung production cross sections of Koch and Motz and of Blumental and Gould are used in order to derive the bremsstrahlung production spectrum in interstellar space down to 10 keV-photon energies. If the low-energy ..gamma..-ray emission, as seen by most observers, is indeed produced by electron bremsstrahlung, then a high interstellar electron flux at MeV energy results, which-at higher energies-connects to the upper limit derived by Cummings, Stone, and Vogt. Such a high low-energy electron flux would be able to explain the ionization rate of 1 x 10/sup -15/ ion pairs (H-atom/sup -1/ s/sup -1/) in H I regions. Because of uncertainties in the low-energy ..gamma..-ray measurements, however, no definite conclusion is possible yet.

  8. New COMPTEL results on pulsar studies at MeV energies

    Science.gov (United States)

    Hermsen, W.; Kuiper, L.; Schoenfelder, V.; Strong, A. W.; Bennett, K.; Much, R.; McConnell, M.; Ryan, J.; Carraminana, A.

    1997-01-01

    The Compton telescope (COMPTEL) onboard the Compton Gamma Ray Observatory (CGRO) detected the pulsar PSR B1951-32 at MeV energies, and found indications of a signal from PSR B0656+14. In the combined spectra from COMPTEL and the energetic gamma ray experiment telescope (EGRET) onboard CGRO, it can be seen that the maximum luminosities of these objects are reached in the COMPTEL energy range. These spectra can be compared with those from four other pulsars observed in MeV energies with COMPTEL. The spectral properties of five of the six pulsars, Vela, PSR B1509-58, PSR B1951-32 and PSR B0656+14, require breaks and bends at MeV energies. The sixth pulsar, the Crab pulsar, approximately follows a power law flux relation from keV to GeV energies. It is concluded that this spectral behavior may play a role in the discrimination between current gamma ray emission models.

  9. 1 MeV, 10 kW DC electron accelerator for industrial applications

    Science.gov (United States)

    Nayak, B.; Acharya, S.; Bhattacharjee, D.; Bakhtsingh, R. I.; Rajan, R.; Sharma, D. K.; Dewangan, S.; Sharma, V.; Patel, R.; Tiwari, R.; Benarjee, S.; Srivastava, S. K.

    2016-03-01

    Several modern applications of radiation processing like medical sterilization, rubber vulcanization, polymerization, cross-linking and pollution control from thermal power stations etc. require D.C. electron accelerators of energy ranging from a few hundred keVs to few MeVs and power from a few kilowatts to hundreds of kilowatts. To match these requirements, a 3 MeV, 30 kW DC electron linac has been developed at BARC, Mumbai and current operational experience of 1 MeV, 10 kW beam power will be described in this paper. The LINAC composed mainly of Electron Gun, Accelerating Tubes, Magnets, High Voltage source and provides 10 kW beam power at the Ti beam window stably after the scanning section. The control of the LINAC is fully automated. Here Beam Optics study is carried out to reach the preferential parameters of Accelerating as well as optical elements. Beam trials have been conducted to find out the suitable operation parameters of the system.

  10. Trends and applications for MeV electrostatic ion beam accelerators

    Science.gov (United States)

    Norton, G. A.; Stodola, S. E.

    2014-08-01

    The 1970s into the 1980s saw a major broadening of applications for electrostatic accelerators. Prior to this time, all accelerators were used primarily for nuclear structure research. In the 70s there was a significant move into production ion implantation with the necessary MeV ion beam analysis techniques such as RBS and ERD. Accelerators are still being built for these materials analysis techniques today. However, there is still a great ongoing expansion of applications for these machines. At the present time, the demand for electrostatic accelerators is near an all time high. The number of applications continues to grow. This paper will touch on some of the current applications which are as diverse as nuclear fission reactor developments and pharmacokinetics. In the field of nuclear engineering, MeV ion beams from electrostatic accelerators are being used in material damage studies and for iodine and actinide accelerator mass spectrometry (AMS). In the field of pharmacokinetics, electrostatic MeV accelerators are being used to detect extremely small amounts of above background 14C. This has significantly reduced the time required to reach first in human studies. These and other applications will be discussed.

  11. Dosimetric verification of a commercial Monte Carlo treatment planning system (VMC++) for a 9 MeV electron beam.

    Science.gov (United States)

    Schiapparelli, P; Zefiro, D; Taccini, G

    2009-05-01

    The aim of this work was to evaluate the performance of the voxel-based Monte Carlo algorithm implemented in the commercial treatment planning system ONCENTRA MASTERPLAN for a 9 MeV electron beam produced by a linear accelerator Varian Clinac 2100 C/D. In order to realize an experimental verification of the computed data, three different groups of tests were planned. The first set was performed in a water phantom to investigate standard fields, custom inserts, and extended treatment distances. The second one concerned standard field, irregular entrance surface, and oblique incidence in a homogeneous PMMA phantom. The last group involved the introduction of inhomogeneities in a PMMA phantom to simulate high and low density materials such as bone and lung. Measurements in water were performed by means of cylindrical and plane-parallel ionization chambers, whereas measurements in PMMA were carried out by the use of radiochromic films. Point dose values were compared in terms of percentage difference, whereas the gamma index tool was used to perform the comparison between computed and measured dose profiles, considering different tolerances according to the test complexity. In the case of transverse scans, the agreement was searched in the plane formed by the intersection of beam axis and the profile (2D analysis), while for percentage depth dose curves, only the beam axis was explored (1D analysis). An excellent agreement was found for point dose evaluation in water (discrepancies smaller than 2%). Also the comparison between planned and measured dose profiles in homogeneous water and PMMA phantoms showed good results (agreement within 2%-2 mm). Profile evaluation in phantoms with internal inhomogeneities showed a good agreement in the case of "lung" insert, while in tests concerning a small "bone" inhomogeneity, a discrepancy was particularly evidenced in dose values on the beam axis. This is due to the inaccurate geometrical description of the phantom that is linked

  12. Nuclear gamma rays from 720-MeV alpha-induced reactions on Al-27 and Si-28

    Science.gov (United States)

    Lieb, B. J.; Plendl, H. S.; Funsten, H. O.; Stronach, C. E.; Lind, V. G.

    1980-01-01

    Prompt gamma rays from the interaction of 720-MeV alpha particles with Al-27 and Si-28 were detected and analyzed to identify residual nuclei and to determine cross sections for production of specific levels. No gamma-ray transitions were detected from nuclei heavier than the target. From Doppler broadening, the momentum of the residual nuclei was estimated. The results are compared with previous results for 140- and 1600-MeV alphas on Al-27 and approximately 200-MeV positive or negative pions on Al-27 and Si-28 and fitted to a spallation-yield formula.

  13. (p,. cap alpha. ) reaction on /sup 98/Mo and /sup 100/Mo. [12. 3 and 15 Mev, angular distributions

    Energy Technology Data Exchange (ETDEWEB)

    Avrigeanu, V.; Bucurescu, D.; Constantinescu, G.; Ivascu, M.; Popescu, D.; Teodorescu, R.

    1975-01-01

    Levels of /sup 95/Nb and /sup 97/Nb were studied with the /sup 98/Mo(p, ..cap alpha..) reaction at 12.3 MeV and the /sup 100/Mo(p, ..cap alpha..) reaction at 15 MeV incident energy, respectively. Angular distributions were determined for the most prominent levels below 2 MeV, and compared with DWBA calculations based on a triton-cluster form factor. The results are compared with level schemes provided by other nuclear reactions. (auth)

  14. Stopping power of liquid water for carbon ions in the energy range between 1 MeV and 6 MeV.

    Science.gov (United States)

    Rahm, J M; Baek, W Y; Rabus, H; Hofsäss, H

    2014-07-21

    The stopping power of liquid water was measured for the first time for carbon ions in the energy range between 1 and 6 MeV using the inverted Doppler shift attenuation method. The feasibility study carried out within the scope of the present work shows that this method is well suited for the quantification of the controversial condensed phased effect in the stopping power for heavy ions in the intermediate energy range. The preliminary results of this work indicate that the stopping power of water for carbon ions with energies prevailing in the Bragg-peak region is significantly lower than that of water vapor. In view of the relatively high uncertainty of the present results, a new experiment with uncertainties less than the predicted difference between the stopping powers of both water phases is planned.

  15. European Collaboration for High-Resolution Measurements of Neutron Cross Sections between 1 MeV and 250 MeV

    CERN Multimedia

    Leal, L C; Kitis, G; Guber, K H; Yuasa nakagawa, K; Koehler, P E; Quaranta, A

    2002-01-01

    The experimental determination of neutron cross section data has always been of primary importance in Nuclear Physics. Many of the salient features of nuclear levels and densities can be determined from the resonant structure of such cross sections and of their decay scheme. An associated importance of precise neutron induced reaction cross sections has resulted from the worldwide interest in Accelerator Driven Systems (ADS) that has emerged at CERN and elsewhere. Many applications, such as accelerator-based transmutation of nuclear waste, energy amplification medical research, astrophysical applications and also fusion research require nuclear data that quantitatively and qualitatively go beyond the presently available traditional evaluation.\\\\ \\\\We consider a spallation driven TOF facility at the CERN-PS with an unprecedented neutron flux (1000 times the existing ones) in the broad energy range between 1 eV and 250 MeV and with very high energy resolution. The present concept for an intense neutron source m...

  16. Measurements of 15.11-MeV gamma-ray flux produced in the reactions C-12(p, p')-C-12*(15.11 MeV) and O-16(p, p' alpha)-C-12*(15.11 MeV)

    Science.gov (United States)

    Lapides, J. R.; Crannell, C. J.; Crannell, H.; Hornyak, W. F.; Seltzer, S. M.; Trombka, J. I.; Wall, N. S.

    1978-01-01

    The flux of 15.11 MeV gamma rays relative to the flux of 4.44 MeV gamma rays which are emitted from the corresponding states of C-12 are a sensitive measure of the spectrum of exciting particles in solar flares and other cosmic sources. Emission of 15.11 MeV gamma rays may result not only from the direct excitation of C-12 but also from the interaction O-16 (p,p' alpha) C-12* sup 15.11 MeV. Although the cross sections for the direct reaction was studied extensively, the cross section for the spallation interaction with O-16 is not reported in the literature. Preliminary measurements demonstrated the feasibility of measuring the production of 15.11 MeV gamma rays by proton interactions with O-16 using the University of Maryland cyclotron facility. For both carbon and oxygen targets the flux of 15.11 MeV gamma rays is being measured relative to the flux of 4.44 MeV gamma rays. The gamma ray emission from de-excitation of the giant dipole resonances is being measured.

  17. On the possibility of two new 'elementary' particles with mass equal to m(k)=1.80339 MeV and m({alpha}-bar{sub gs})=26.180339 MeV

    Energy Technology Data Exchange (ETDEWEB)

    El Naschie, M.S

    2004-05-01

    To sustain the global symplictic structure of the VAK of vacuum fluctuation, transfinite quantities of energy of the order of k=phi{sup 3}(1-phi{sup 3})=0.18033989 MeV and k{sub 0}=phi{sup 5}(1-phi{sup 5})=0.08203939 MeV must be added to it. In the ten dimensional core of the super string space this leads to the formation of particle masses of the order of m(k)=(10)(k)=1.8033989 MeV. Using {epsilon}{sup (}'{infinity}') theory and the M-dualities between high and low energy domains, one could make a second prediction regarding a unification-related particle m({alpha}-bar{sub gs})=10/2(m(k))(phi+1){sup 7}=26.18033989 MeV. The possible experimental ramifications of the theory are also discussed.

  18. Cross section ratio and angular distributions of the reaction p + d → {sup 3}He + η at 48.8 MeV and 59.8 MeV excess energy

    Energy Technology Data Exchange (ETDEWEB)

    Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Hoeistad, B.; Johansson, T.; Marciniewski, P.; Redmer, C.F.; Wolke, M.; Zlomanczuk, J. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Department of Nuclear Physics, Warsaw (Poland); Bardan, W.; Ciepal, I.; Czerwinski, E.; Hodana, M.; Jany, A.; Jany, B.R.; Jarczyk, L.; Kamys, B.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Ozerianska, I.; Podkopal, P.; Rudy, Z.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J. [Jagiellonian University, Institute of Physics, Krakow (Poland); Bashkanov, M.; Clement, H.; Doroshkevich, E.; Perez del Rio, E.; Pricking, A.; Skorodko, T.; Wagner, G.J. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Physikalisches Institut der Universitaet Tuebingen, Kepler Center fuer Astro- und Teilchenphysik, Tuebingen (Germany); Bergmann, F.S.; Demmich, K.; Goslawski, P.; Huesken, N.; Khoukaz, A.; Passfeld, A.; Taeschner, A. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Berlowski, M.; Stepaniak, J. [National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Bhatt, H.; Lalwani, K.; Varma, R. [Indian Institute of Technology Bombay, Department of Physics, Mumbai, Maharashtra (India); Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Maier, R.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Stroeher, H.; Wurm, P.; Zurek, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Coderre, D.; Ritman, J. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (Germany); Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P. [Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Forschungszentrum Juelich, Zentralinstitut fuer Engineering, Elektronik und Analytik, Juelich (Germany); Eyrich, W.; Hauenstein, F.; Krapp, M.; Zink, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Fedorets, P. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Foehl, K. [Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Goswami, A. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (India); Grigoryev, K. [Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); RWTH Aachen, III. Physikalisches Institut B, Physikzentrum, Aachen (Germany); Petersburg Nuclear Physics Institute, High Energy Physics Division, Leningrad district (Russian Federation); Kirillov, D.A.; Piskunov, N.M. [Joint Institute for Nuclear Physics, Veksler and Baldin Laboratory of High Energiy Physics, Moscow region (Russian Federation); Klos, B.; Stephan, E.; Weglorz, W. [University of Silesia, August Chelkowski Institute of Physics, Katowice (Poland); Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A. [Polish Academy of Sciences, The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Kupsc, A.; Pszczel, D. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Mikirtychiants, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (DE); Petersburg Nuclear Physics Institute, High Energy Physics Division, Leningrad district (RU); Pyszniak, A. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (SE); Jagiellonian University, Institute of Physics, Krakow (PL); Roy, A. [Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (IN); Sawant, S. [Indian Institute of Technology Bombay, Department of Physics, Mumbai, Maharashtra (IN); Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Serdyuk, V. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Joint Institute for Nuclear Physics, Dzhelepov Laboratory of Nuclear Problems, Moscow region (RU); Sopov, V. [State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (RU); Yamamoto, A. [High Energy Accelerator Research Organization KEK, Tsukuba, Ibaraki (JP); Yurev, L. [Joint Institute for Nuclear Physics, Dzhelepov Laboratory of Nuclear Problems, Moscow region (RU); Zabierowski, J. [National Centre for Nuclear Research, Department of Cosmic Ray Physics, Lodz (PL); Collaboration: WASA-at-COSY Collaboration

    2014-06-15

    We present new data for angular distributions and on the cross section ratio of the p+d → {sup 3}He + η reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Juelich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval. (orig.)

  19. Cross section ratio and angular distributions of the reaction p + d → 3He + η at 48.8 MeV and 59.8 MeV excess energy

    Science.gov (United States)

    Adlarson, P.; Augustyniak, W.; Bardan, W.; Bashkanov, M.; Bergmann, F. S.; Berłowski, M.; Bhatt, H.; Büscher, M.; Calén, H.; Ciepał, I.; Clement, H.; Coderre, D.; Czerwiński, E.; Demmich, K.; Doroshkevich, E.; Engels, R.; Erven, A.; Erven, W.; Eyrich, W.; Fedorets, P.; Föhl, K.; Fransson, K.; Goldenbaum, F.; Goslawski, P.; Goswami, A.; Grigoryev, K.; Gullström, C.-O.; Hauenstein, F.; Heijkenskjöld, L.; Hejny, V.; Hodana, M.; Höistad, B.; Hüsken, N.; Jany, A.; Jany, B. R.; Jarczyk, L.; Johansson, T.; Kamys, B.; Kemmerling, G.; Khan, F. A.; Khoukaz, A.; Kirillov, D. A.; Kistryn, S.; Kłos, B.; Kleines, H.; Krapp, M.; Krzemień, W.; Kulessa, P.; Kupść, A.; Lalwani, K.; Lersch, D.; Lorentz, B.; Magiera, A.; Maier, R.; Marciniewski, P.; Mariański, B.; Mikirtychiants, M.; Morsch, H.-P.; Moskal, P.; Ohm, H.; Ozerianska, I.; Passfeld, A.; Perez del Rio, E.; Piskunov, N. M.; Podkopał, P.; Prasuhn, D.; Pricking, A.; Pszczel, D.; Pysz, K.; Pyszniak, A.; Redmer, C. F.; Ritman, J.; Roy, A.; Rudy, Z.; Sawant, S.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Siudak, R.; Skorodko, T.; Skurzok, M.; Smyrski, J.; Sopov, V.; Stassen, R.; Stepaniak, J.; Stephan, E.; Sterzenbach, G.; Stockhorst, H.; Ströher, H.; Szczurek, A.; Täschner, A.; Trzciński, A.; Varma, R.; Wagner, G. J.; Węglorz, W.; Wolke, M.; Wrońska, A.; Wüstner, P.; Wurm, P.; Yamamoto, A.; Yurev, L.; Zabierowski, J.; Zieliński, M. J.; Zink, A.; Złomańczuk, J.; Żuprański, P.; Żurek, M.

    2014-06-01

    We present new data for angular distributions and on the cross section ratio of the p+d → 3He + η reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Jülich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval.

  20. Constraining the 6.05 MeV 0$^+$ and 6.13 MeV 3$^-$ cascade transitions in the $^{12}$C($\\alpha$,$\\gamma$)$^{16}$O reaction using the Asymptotic Normalization Coefficients

    CERN Document Server

    Avila, M L; Koshchiy, E; Baby, L T; Belarge, J; Kemper, K W; Kuchera, A N; Mukhamedzhanov, A M; Santiago-Gonzalez, D; Uberseder, E

    2014-01-01

    Background. The $^{12}$C($\\alpha,\\gamma$)$^{16}$O reaction plays a fundamental role in astrophysics because its cross section near 300 keV in c.m. determines the $^{12}$C/$^{16}$O ratio at the end of the helium burning stage of stellar evolution. The astrophysically desired accuracy of better than 10\\% has not been achieved. Cascade $\\gamma$ transitions through the excited states of $^{16}$O are contributing to the uncertainty. Purpose. To measure the Asymptotic Normalization Coefficients (ANCs) for the 0$^+$ (6.05 MeV) and 3$^-$ (6.13 MeV) excited states in $^{16}$O and provide constraints on the cross section for the corresponding cascade transitions. Method. The ANCs were measured using the $\\alpha$-transfer reaction $^{12}$C($^6$Li,$d$)$^{16}$O performed at sub-Coulomb energies for both the entrance and exit channels. Results. The ANCs for the 0$^+$(6.05 MeV), 3$^-$(6.13 MeV), 2$^+$(6.92 MeV) and 1$^-$(7.12 MeV) states in $^{16}$O have been measured. The contribution of the 0$^+$ and 3$^-$ cascade transit...

  1. Serenoa repens associated with Urtica dioica (ProstaMEV) and curcumin and quercitin (FlogMEV) extracts are able to improve the efficacy of prulifloxacin in bacterial prostatitis patients: results from a prospective randomised study.

    Science.gov (United States)

    Cai, Tommaso; Mazzoli, Sandra; Bechi, Adriano; Addonisio, Patrizia; Mondaini, Nicola; Pagliai, Roberto Castricchi; Bartoletti, Riccardo

    2009-06-01

    We report the results of a prospective randomised study to evaluate the therapeutic effect of Serenoa repens, Urtica dioica (ProstaMEV), quercitin and curcumin (FlogMEV) extracts associated with prulifloxacin in patients affected by chronic bacterial prostatitis (CBP). From a whole population of 284 patients, 143 patients affected by CBP [National Institutes of Health (NIH) class II prostatitis] were enrolled. All patients received prulifloxacin 600 mg daily for 14 days, in accordance with antibiogram results. Patients were split into two groups: Group A received prulifloxacin associated with ProstaMEV and FlogMEV; Group B received only antibiotic therapy. Microbiological and clinical efficacies were tested by two follow-up visits at 1 month and 6 months, respectively. Quality of life (QoL) was measured using the NIH Chronic Prostatitis Symptom Index (CPSI) and International Prostatic Symptom Score (IPSS) questionnaires. Group A comprised 106 patients and Group B comprised 37 patients. One month after treatment, 89.6% of patients who had received prulifloxacin associated with ProstaMEV and FlogMEV did not report any symptoms related to CBP, whilst only 27% of patients who received antibiotic therapy alone were recurrence-free (P patients in Group A had recurrence of disease whilst two patients in Group B did. Questionnaire results demonstrated statistically significant differences between groups (all P patients affected by CBP.

  2. First observation of spin dichroism with deuterons up to 20 MeV in a carbon target

    CERN Document Server

    Baryshevsky, V; Engels, R; Rathmann, F; Seyfarth, H; Ströher, H; Ullrich, T; D"uweke, C; Emmerich, R; Imig, A; Ley, J; Schieck, H P; Schulze, R; Tenckhoff, G; Weske, C; Mikirtytchiants, M; Vasilev, A

    2005-01-01

    The first observation of the phenomenom of deuteron spin dichroism in the energy region of 6-20 MeV is described. Experimental values of this effect for deuterons after passage of an unpolarized carbon target are reported.

  3. Slow running of the Gradient Flow coupling from 200 MeV to 4 GeV in $N_{\\rm f}=3$ QCD

    CERN Document Server

    Dalla Brida, Mattia; Korzec, Tomasz; Ramos, Alberto; Sint, Stefan; Sommer, Rainer

    2017-01-25

    Using a finite volume Gradient Flow (GF) renormalization scheme with Schr\\"odinger Functional (SF) boundary conditions, we compute the non-perturbative running coupling in the range $2.2 \\lesssim {\\bar g}_\\mathrm{GF}^2(L) \\lesssim 13$. Careful continuum extrapolations turn out to be crucial to reach our high accuracy. The running of the coupling is always between one-loop and two-loop and very close to one-loop in the region of $200\\,{\\rm MeV} \\lesssim \\mu=1/L \\lesssim 4\\,{\\rm GeV}$. While there is no convincing contact to two-loop running, we match non-perturbatively to the SF coupling with background field. In this case we know the $\\mu$ dependence up to $\\sim 100\\,{\\rm GeV}$ and can thus connect to the $\\Lambda$-parameter.

  4. Conceptual design for a neutron imaging system for thick target analysis operating in the 10-15 MeV energy range

    Energy Technology Data Exchange (ETDEWEB)

    Dietrich, F.; Hall, J.; Logan, C.

    1996-09-11

    Fast neutron imaging offers the potential to be a powerful non- destructive inspection tool for evaluating the integrity of thick sealed targets. This is particularly true in cases where one is interested in detecting voids, cracks or other defects in low-Z materials (e.g. plastics, ceramics, salts, etc.) which are shielded by thick, high-Z parts. In this paper we present the conceptual design for a neutron imaging system for use in the 10 - 15 MeV energy range and discuss potential applications in the area of nuclear stockpile steward- ship. The background of this project, currently under development at LLNL, will be outlined and computer simulations will be presented which predict system performance. Efforts to assess technical risks involved in the development of the system will be discussed and the results of a recent experiment designed to evaluate background radiation levels will also be presented.

  5. Calculation of (p,γ and (p,α nuclear reaction cross sections in stars up to 10 MeV

    Directory of Open Access Journals (Sweden)

    Tel Eyyup

    2016-01-01

    Full Text Available In Knowledge of the proton-proton (p-p chain and CNO cycle are required for the evolution of main sequence stars during the early formation of the universe. In this study, we summarized the excitation functions of (p,γ and (p,α reactions for 7Be(p,γ8B, 12C(p,γ13N, 13C(p,γ14N, 14N(p,γ15O and 15N(p,α15O in p-p chain and CNO cycle using EMPIRE and TALYS computer up to 10 MeV. The calculated data on nuclear fusion cross sections in hydrogen-burning stars were compared with theoretical TENDL-2014 and ENDF/B-VII data from EXFOR. The calculation results show closed agreement between the calculations and the data from literature.

  6. Measurement of 58Fe (p , n)58Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV

    Science.gov (United States)

    Ghosh, Reetuparna; Badwar, Sylvia; Lawriniang, Bioletty; Jyrwa, Betylda; Naik, Haldhara; Naik, Yeshwant; Suryanarayana, Saraswatula Venkata; Ganesan, Srinivasan

    2017-08-01

    The 58Fe (p , n)58Co reaction cross-section within Giant Dipole Resonance (GDR) region i.e. from 3.38 to 19.63 MeV was measured by stacked-foil activation and off-line γ-ray spectrometric technique using the BARC-TIFR Pelletron facility at Mumbai. The present data were compared with the existing literature data and found to be in good agreement. The 58Fe (p , n)58Co reaction cross-section as a function of proton energy was also theoretically calculated by using the computer code TALYS-1.8 and found to be in good agreement, which shows the validity of the TALYS-1.8 program.

  7. Calculation of (p,γ) and (p,α) nuclear reaction cross sections in stars up to 10 MeV

    Science.gov (United States)

    Tel, Eyyup; Sahan, Muhittin; Sarpun, Ismail Hakki; Okur, Sureyya Gulistan

    2016-11-01

    In Knowledge of the proton-proton (p-p) chain and CNO cycle are required for the evolution of main sequence stars during the early formation of the universe. In this study, we summarized the excitation functions of (p,γ) and (p,α) reactions for 7Be(p,γ)8B, 12C(p,γ)13N, 13C(p,γ)14N, 14N(p,γ)15O and 15N(p,α)15O in p-p chain and CNO cycle using EMPIRE and TALYS computer up to 10 MeV. The calculated data on nuclear fusion cross sections in hydrogen-burning stars were compared with theoretical TENDL-2014 and ENDF/B-VII data from EXFOR. The calculation results show closed agreement between the calculations and the data from literature.

  8. Calculations of (n,2n reaction cross sections for 74,76,78,80,82Se up to 20 MeV

    Directory of Open Access Journals (Sweden)

    Şahan Halide

    2016-01-01

    Full Text Available In the present work, the excitation functions of (n,2n reactions for five isotopes of selenium (74,76,78,80,82Se are calculated using ALICE/ASH, EMPIRE-3.2.2, PCROSS, and TALYS 1.6 computer codes based on statistical model up to 20 MeV. The theoretical calculations provide information of the (n,2n excitation functions with the increasing target neutron number of selenium element. The calculated cross-sections were compared with experimental data from EXFOR and also with the crosssections estimated with semi empirical formula developed by Tet et al. (2008 [18]. Results show a reasonably good agreement between the calculations and the experimental data from literature.

  9. Simplified method for deducing high-energy neutron spectra between 1 and 100 MeV using Foil-Activation Method

    Energy Technology Data Exchange (ETDEWEB)

    Kasugai, Y.; Matsuda, N.; Sakamoto, Y.; Nakashima, H. [Japan Atomic Energy Agency, Tokai-mura, Ibaraki-ken 319-1195 (Japan); Yashima, H. [Research Reactor Inst., Kyoto Univ., Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Matsumura, H.; Iwase, H.; Hirayama, H. [High Energy Accelerator Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Mokhov, N.; Leveling, A.; Boehnlein, D.; Vaziri, K.; Lauten, G. [Fermi National Accelerator Laboratory, Batavia, IL 87545 (United States); Oishi, K. [Shimizu Corporation, 4-17, Echujima 3-chome, Koto-ku, Tokyo 135-8530 (Japan); Nakamura, T. [Tohoku Univ., Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578 (Japan)

    2011-07-01

    The Japanese and American Study of Muon Interaction and Neutron detection (JASMIN) collaboration, has been conducting shielding experiments using the Fermilab anti-proton target station (Pbar) shielding assembly. A multi-foil technique was used to measure the high energy neutron spectra, in the range of 1 to 100 MeV, for the target station shielding configuration. The neutron spectra were de-convoluted using a new fitting method. This method is based on the assumption that a neutron spectrum can be expressed as a simple sum of two exponentials. The validity of the fitting method was confirmed by comparison with the results obtained using SAND-II computer code and theoretical calculations. Finally, it was found that there are simple correlations between reaction rates and the adjustable parameters in the fitting function. (authors)

  10. Measurements of neutron spectra from iron and boron—in—polyethylene bomareded with 14MeV nuetrons

    Institute of Scientific and Technical Information of China (English)

    ZhouYu-Qing; ChenYuan; 等

    1997-01-01

    The leakage spectra of 14MeV neutrons from spheres of iron and boron-inpolyethylene with three differnet mass ratios of boron carbide to polyethylene were measured over the energy range of 20 keV to 16MeV by using proton recoil method.The integral leakages and removal cross sections at different lower cut-off energy were given.

  11. Dual sightline measurements of MeV range deuterons with neutron and gamma-ray spectroscopy at JET

    DEFF Research Database (Denmark)

    Eriksson, J.; Nocente, M.; Binda, F.

    2015-01-01

    Observations made in a JET experiment aimed at accelerating deuterons to the MeV range by third harmonic radio-frequency (RF) heating coupled into a deuterium beam are reported. Measurements are based on a set of advanced neutron and gamma-ray spectrometers that, for the first time, observe the p......, more generally, to studies of the energy distribution of ions in the MeV range in high performance deuterium and deuterium-tritium plasmas....

  12. Neutron emission cross sections on sup 93 Nb and sup 209 Bi at 20 MeV incident energy

    Energy Technology Data Exchange (ETDEWEB)

    Marcinkowski, A.; Rapaport, J.; Finlay, R.; Aslanoglou, X. (Ohio Univ., Athens, OH (USA)); Kielan, D. (Soltan Inst. for Nuclear Studies, Warsaw (Poland))

    1991-07-29

    Double-differential neutron emission cross sections at 20 MeV incident energy have been studied for monoisotopic samples of {sup 93}Nb and {sup 209}Bi. Time-of-flight spectra were taken at several angles between 15{sup 0} and 153{sup 0} using a beam-swinger spectrometer. The data are averaged over 0.5 MeV energy bins and compared with quantum-mechanical, statistical multistep calculations. (orig.).

  13. Constraints on gamma-ray line and continuum emission from the Galactic Center Region at MeV Energies

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, R.; v. Ballmoos, P.; Schoenfelder, V.

    1988-09-25

    MPE Compton Telescope observations of MeV radiation from the direction of the Galactic Center lead to constraints on the central source and on diffuse processes in the Galaxy: The extent of 1.8 MeV line emission from /sup 26/Al suggests an /sup 26/Al production process with pronounced concentration towards the Galactic Center. The absence of other ..gamma..-ray lines constrains nucleosynthesis and cosmic ray excitation parameters in the Galaxy.

  14. Personal dose equivalent conversion coefficients for neutron fluence over the energy range of 20 to 250 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Mclean, Thomas D [Los Alamos National Laboratory; Justus, Alan L [Los Alamos National Laboratory; Gadd, S Milan [Los Alamos National Laboratory; Olsher, Richard H [RP-2; Devine, Robert T [RP-2

    2009-01-01

    Monte Carlo simulations were performed to extend existing neutron personal dose equivalent fluence-to-dose conversion coefficients to an energy of 250 MeV. Presently, conversion coefficients, H(p,slab)(10,alpha)/Phi, are given by ICRP-74 and ICRU-57 for a range of angles of radiation incidence (alpha = 0, 15, 30, 45, 60 and 75 degrees ) in the energy range from thermal to 20 MeV. Standard practice has been to base operational dose quantity calculations <20 MeV on the kerma approximation, which assumes that charged particle secondaries are locally deposited, or at least that charged particle equilibrium exists within the tally cell volume. However, with increasing neutron energy the kerma approximation may no longer be valid for some energetic secondaries such as protons. The Los Alamos Monte Carlo radiation transport code MCNPX was used for all absorbed dose calculations. Transport models and collision-based energy deposition tallies were used for neutron energies >20 MeV. Both light and heavy ions (HIs) (carbon, nitrogen and oxygen recoil nuclei) were transported down to a lower energy limit (1 keV for light ions and 5 MeV for HIs). Track energy below the limit was assumed to be locally deposited. For neutron tracks <20 MeV, kerma factors were used to obtain absorbed dose. Results are presented for a discrete set of angles of incidence on an ICRU tissue slab phantom.

  15. Formation of ion tracks in amorphous silicon nitride films with MeV C{sub 60} ions

    Energy Technology Data Exchange (ETDEWEB)

    Kitayama, T.; Morita, Y.; Nakajima, K. [Department of Micro Engineering, Kyoto University, Kyoto 606-8501 (Japan); Narumi, K.; Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Matsuda, M.; Sataka, M. [Nuclear Science Research Institute, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Tsujimoto, M.; Isoda, S. [Institute for Integrated Cell-Material Sciences, Kyoto University, Kyoto 606-8501 (Japan); Toulemonde, M. [CIMAP-GANIL (CEA-CNRS-ENSICAEN-Université de Caen Basse Normandie), Bd. H. Becquerel, 14070 Caen (France); Kimura, K., E-mail: kimura@kues.kyoto-u.ac.jp [Department of Micro Engineering, Kyoto University, Kyoto 606-8501 (Japan)

    2015-08-01

    Amorphous silicon nitride (a-SiN) films (thickness 5–100 nm) were irradiated with 0.12–5 MeV C{sub 60}, 100 MeV Xe, 200 MeV Kr, and 200 and 420 MeV Au ions. Ion tracks were clearly observed using high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) except for 100 MeV Xe and 200 MeV Kr. The observed HAADF-STEM images showed that the ion tracks consist of a low density core (0.5–2 nm in radius) and a high density shell (several nm in radius). The observed core and shell radii are not simply correlated with the electronic energy loss indicating that the nuclear energy loss plays an important role in the both core and shell formations. The observed track radii were well reproduced by the unified thermal spike model with two thresholds for shell and core formations.

  16. Elastic neutron scattering studies at 96 MeV for transmutation.

    Science.gov (United States)

    Osterlund, M; Blomgren, J; Hayashi, M; Mermod, P; Nilsson, L; Pomp, S; Ohrn, A; Prokofiev, A V; Tippawan, U

    2007-01-01

    Elastic neutron scattering from (12)C, (14)N, (16)O, (28)Si, (40)Ca, (56)Fe, (89)Y and (208)Pb has been studied at 96 MeV in the10-70 degrees interval, using the SCANDAL (SCAttered Nucleon Detection AssembLy) facility. The results for (12)C and (208)Pb have recently been published, while the data on the other nuclei are under analysis. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. A novel method for normalisation of the absolute scale of the cross section has been used. The estimated normalisation uncertainty, 3%, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. Elastic neutron scattering is of utmost importance for a vast number of applications. Besides its fundamental importance as a laboratory for tests of isospin dependence in the nucleon-nucleon, and nucleon-nucleus, interaction, knowledge of the optical potentials derived from elastic scattering come into play in virtually every application where a detailed understanding of nuclear processes is important. Applications for these measurements are dose effects due to fast neutrons, including fast neutron therapy, as well as nuclear waste incineration and single event upsets in electronics. The results at light nuclei of medical relevance ((12)C, (14)N and (16)O) are presented separately. In the present contribution, results on the heavier nuclei are presented, among which several are of relevance to shielding of fast neutrons.

  17. Large scale silver nanowires network fabricated by MeV hydrogen (H+) ion beam irradiation

    Science.gov (United States)

    Honey, S.; Naseem, S.; Ishaq, A.; Maaza, M.; Bhatti, M. T.; Wan, D.

    2016-04-01

    A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H+) ion beam irradiation. Ag-NWs are irradiated under H+ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H+ ion beam-induced welding of Ag-NWs at intersecting positions. H+ ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H+ ion beam, and networks are optically transparent. Morphology also remains stable under H+ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H+ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices. Project supported by the National Research Foundation of South Africa (NRF), the French Centre National pour la Recherche Scientifique, iThemba-LABS, the UNESCO-UNISA Africa Chair in Nanosciences & Nanotechnology, the Third World Academy of Science (TWAS), Organization of Women in Science for the Developing World (OWSDW), the Abdus Salam ICTP via the Nanosciences African Network (NANOAFNET), and the Higher Education Commission (HEC) of Pakistan.

  18. Determining the Effects of EMIC Waves on Precipitating MeV Electrons during Strom Main Phases

    Science.gov (United States)

    Chen, Y.

    2015-12-01

    Theoretic studies have suggested that electromagnetic ion cyclotron (EMIC) waves can cause significant precipitation of ~MeV electrons, supposedly accounting for the fast dropouts of outer-belt electrons during storm main phases. Usually the resonance between left-hand polarized EMIC with electrons with moderate energy is unlikely due to their opposite polarizations, while resonance with highly relativistic electrons do occur and cause electrons to precipitate into the atmosphere through pitch-angle scattering. Several previous studies on observations find a close relation between the two phenomena, e.g., Cliverd et al. [2007], Sandanger et al. [2007], and Miyoshi et al. [2008], while others find otherwise, e.g., Meredith et al. [2011]; recently, more observational evidence supporting the connection has been reported (e.g., Li et al. [2014] and Blum et al. [2015]). However, whether and under what favoring conditions EMIC waves cause rapid dropouts of relativistic electrons during storm main phases remain unresolved questions. Here, using latest wave and electron data from multiple missions including Van Allen Probes, BARREL, and NOAA POES, we systemically examine the relation between EMIC waves and MeV electron precipitation. We first construct two independent event lists for intensified EMIC waves and enhancements of MeV electron precipitation, respectively. Then we cross check the two lists to identify if any significant correlation exists in between, and further characterize the wave effectiveness in terms of L-shell, MLT, resonance energy, as well as the background plasma conditions. Results from this study will advance our knowledge about the loss mechanism of outer-belt electrons, thus laying down another stepping stone towards high-fidelity physics-based models for radiation belts.

  19. The Spectrum of Isotropic Diffuse Gamma-Ray Emission Between 100 Mev and 820 Gev

    Science.gov (United States)

    Ackermann, M.; Ajello, M.; Albert, A.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Brandt, T. J.; Hays, E.; Perkins, J. S.

    2014-01-01

    The gamma-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, and a residual all-sky emission component commonly called the isotropic diffuse gamma-ray background (IGRB). The IGRB comprises all extragalactic emissions too faint or too diffuse to be resolved in a given survey, as well as any residual Galactic foregrounds that are approximately isotropic. The first IGRB measurement with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) used 10 months of sky-survey data and considered an energy range between 200 MeV and 100 GeV. Improvements in event selection and characterization of cosmic-ray backgrounds, better understanding of the diffuse Galactic emission, and a longer data accumulation of 50 months, allow for a refinement and extension of the IGRB measurement with the LAT, now covering the energy range from 100 MeV to 820 GeV. The IGRB spectrum shows a significant high-energy cutoff feature, and can be well described over nearly four decades in energy by a power law with exponential cutoff having a spectral index of 2.32 plus or minus 0.02 and a break energy of (279 plus or minus 52) GeV using our baseline diffuse Galactic emission model. The total intensity attributed to the IGRB is (7.2 plus or minus 0.6) x 10(exp -6) cm(exp -2) s(exp -1) sr(exp -1) above 100 MeV, with an additional +15%/-30% systematic uncertainty due to the Galactic diffuse foregrounds.

  20. Investigation of (d,x) nuclear reactions on natural ytterbium up to 24 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Khandaker, Mayeen Uddin, E-mail: mu_khandaker@um.edu.my [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Haba, Hiromitsu [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Otuka, Naohiko [Nuclear Data Section, Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, A-1400 Vienna (Austria); Usman, Ahmed Rufa’i [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-09-15

    Production cross-sections of the {sup nat}Yb(d,x){sup 169,170,171,172,173,174m,174,176m,177g}Lu and {sup 169,175,177}Yb reactions have been measured from a 24-MeV deuteron energy down to their respective thresholds by using a stacked-foil activation technique combined with high resolution γ-ray spectrometry. Our new experimental data extended the experimental database toward the lower energy region for {sup 169}Yb, {sup 171}Lu, {sup 172}Lu, and {sup 176m}Lu, and the higher region for {sup 174}Lu, {sup 176m}Lu, and {sup 177}Yb. An overall good agreement is found with some of the earlier measurements, whereas a partial agreement is obtained with the theoretical data extracted from the TENDL-2013 library. The (d,p) channel contribution underestimated by the TENDL-2013 library is successfully reproduced in the global renormalization by Ignatyuk for the FENDL-3.0 library. The production cross-sections of {sup 175}Yb available in the literature were revised based on the latest γ-ray intensity adopted in 2004. Physical thick target yields for the investigated reaction products were also deduced and compared with the directly measured ones in the literature. The derived thick target yields for {sup 173}Lu and {sup 174g}Lu are higher than the directly measured ones by Dmitriev et al. at 22 MeV. The deduced yield curves indicate that a low energy (<11 MeV) cyclotron and a highly enriched {sup 176}Yb target could be used to obtain {sup 177g}Lu with negligible impurity from {sup 177m}Lu.

  1. A diamond 14 MeV neutron energy spectrometer with high energy resolution

    Energy Technology Data Exchange (ETDEWEB)

    Shimaoka, Takehiro, E-mail: t.shimaoka@eng.hokudai.ac.jp; Kaneko, Junichi H.; Tsubota, Masakatsu; Shimmyo, Hiroaki [Graduate School of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-8628 (Japan); Ochiai, Kentaro [Fusion Research and Development Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Chayahara, Akiyoshi; Umezawa, Hitoshi; Shikata, Shin-ichi [National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577 (Japan); Watanabe, Hideyuki [National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Isobe, Mitsutaka; Osakabe, Masaki [National Institute for Fusion Science, 322-6, Oroshi-cho, Toki-City, Gifu 509-5292 (Japan)

    2016-02-15

    A self-standing single-crystal chemical vapor deposited diamond was obtained using lift-off method. It was fabricated into a radiation detector and response function measurements for 14 MeV neutrons were taken at the fusion neutronics source. 1.5% of high energy resolution was obtained by using the {sup 12}C(n, α){sup 9}Be reaction at an angle of 100° with the deuteron beam line. The intrinsic energy resolution, excluding energy spreading caused by neutron scattering, slowing in the target and circuit noises was 0.79%, which was also the best resolution of the diamond detector ever reported.

  2. The Gent University 15 MeV high-current linear electron accelerator facility

    Science.gov (United States)

    Mondelaers, W.; Van Laere, K.; Goedefroot, A.; Van den Bossche, K.

    1996-01-01

    The Gent University 15 MeV 20kW linear electron accelerator facility was initially designed for fundamental nuclear physics research. During the last years a large effort has been devoted to the expansion of the range of machine applications in view of a new extensive experimental programme in the fields of atomic and solid-state physics, biomaterials research, polymer chemistry, space research, food technology, high-dose dosimetry and radiation therapy. The accelerator facility in its present configuration, the peripheral equipment and the experimental programme are described with emphasis on the original features.

  3. Response of a chevron microchannel plate to 2.5 and 14 MeV neutrons

    Science.gov (United States)

    Medley, S. S.; Persing, R.

    1981-10-01

    The response of a large area (4.6×13 cm) multianode channel electron multiplier array (CEMA) detector to energetic neutrons was investigated. The measured neutron detection efficiencies of the chevron microchannel plate (MCP) were 1.7×10-3 and 6.4×10-3 counts/neutron, respectively, for 2.5 MeV-DD and 14 MeV-DT neutrons. The apparently higher efficiency observed for the 14 MeV neutrons is attributed to neutron-induced background gamma radiation.

  4. Proton induced reactions on natural U at 62.9 MeV

    CERN Document Server

    Guertin, A; Rivière, G; Eudes, P; Haddad, F; Lebrun, C; Kirchner, T; Le Brun, C; Lecolley, F R; Lecolley, J F; Louvel, M; Lefèbvres, F; Marie, N; Varignon, C; Ledoux, X; Patin, Y; Pras, P; Delbar, T; Ninane, A; Stuttgé, L; Hanappe, F

    2002-01-01

    Double differential cross sections (DDCS) for light charged particles (proton, deuteron, triton, 3He, alpha) and neutrons produced by a proton beam impinging on a 238U target at 62.9 MeV were measured at the CYCLONE facility in Louvain-la-Neuve (Belgium). These measurements have been performed using two independent experimental set-ups ensuring neutron (DeMoN counters) and light charged particles (Si-Si-CsI telescopes) detection. The charged particle data were measured at 11 different angular positions from 25 degrees to 140 degrees allowing the determination of angle differential, energy differential and total production cross sections.

  5. Calibration of NIF neutron detectors in the energy region E<14 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, G J; Moran, M J; Koch, J A; Phillips, T W; Glebov, V Y; Sangster, T C; Stoeckl, C; Wender, S A; Morse, E C

    2004-04-09

    We examine various options for calibration of NIF neutron detectors in the energy region E<14 MeV. These options include: downscatter of D-T fusion neutrons using plastic targets; nuclear reactions at a Tandem Van de Graaf accelerator; and ''white'' neutrons from a pulsed spallation source. As an example of the spallation option, we present some calibration data that was recently obtained with a single crystal CVD diamond detector at the Weapons Neutron Research facility (WNR) at LANL.

  6. Polarization sensitivity of a segmented HPGe detector up to 10 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Hutter, C.; Babilon, M.; Bayer, W.; Galaviz, D.; Hartmann, T.; Mohr, P.; Mueller, S.; Rochow, W.; Savran, D.; Sonnabend, K.; Vogt, K.; Volz, S.; Zilges, A. E-mail: zilges@ikp.tu-darmstadt.de

    2002-08-21

    Linear {gamma}-ray polarization can be measured using segmented germanium detectors. The polarization sensitivity of the Compton scattering process leads to asymmetries in the signals of a segmented detector. We have measured the polarization sensitivity of a four-fold segmented large volume germanium detector up to photon energies of approximately 10 MeV for the first time. The detector and its performance are compared to smaller Compton polarimeters which have been analyzed in previous work. A possible application of the described Compton polarimeter will be parity assignments in photon scattering experiments.

  7. High brightness 50 MeV Cyclotron for Accelerator-Driven Subcritical Fission

    Science.gov (United States)

    Assadi, Saeed; Badgley, Karie; Mann, Thomas; McIntyre, Peter; Pogue, Nathaniel; Sattarov, Akhdiyor

    2011-10-01

    The Accelerator Research Lab at Texas A&M University is developing new accelerator technology for a high-brightness, high-current cyclotron with capabilities that will be beneficial for applications to accelerator-driven subcritical fission, medical isotope production, and proton therapy. As a first embodiment of the technology, we are developing a detailed design for TAMU-50, a 50 MeV, 5 mA proton cyclotron with high beam brightness. In this presentation we present devices and beamline components for injection, extraction, controls and diagnostics. We emphasize the system integration and implementation of TAMU-50 for production of medical radioisotopes.

  8. Dosimetric characterization of CVD diamonds irradiated with 62 MeV proton beams

    Energy Technology Data Exchange (ETDEWEB)

    Cirrone, G.A.P. [Laboratori Nazionali del Sud, INFN, Catania (Italy)]. E-mail: cirrone@lns.infn.it; Cuttone, G. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Lo Nigro, S. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Dipartimento di Fisica ed Astronomia, Universita di Catania (Italy); CSFNSM Centro Siciliano di Fisica Nucleare e Struttura della MAteria, Catania (Italy); Mongelli, V. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Scuola di Specializzazione in Fisica Sanitaria, Universita di Catania (Italy); CSFNSM Centro Siciliano di Fisica Nucleare e Struttura della MAteria, Catania (Italy); Raffaele, L. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Sabini, M.G. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Azienda Ospedaliera Cannizzaro, Catania (Italy); Valastro, L. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Scuola di Specializzazione in Fisica Sanitaria, Universita di Catania (Italy); Bucciolini, M. [Dipartimento di Fisiopatologia Clinica, Universita di Florence (Italy); Onori, S. [Istituto Superiore di Sanita, Rome (Italy)

    2005-10-21

    Diamond is potentially a very suitable material for use as on-line radiation dosimeter. Recent advances in the synthesis of polycrystalline diamond by chemical vapor deposition (CVD) techniques have produced material with electronic properties suitable for dosimetry applications. In this work the possibility to use a segmented commercial CVD detector in the dosimetry of proton beams has been investigated. The response as function of dose, dose rate, the priming and the rise time have been investigated thoroughly. This study shows the suitability of CVD diamond for dosimetry of clinical 62 MeV proton beams.

  9. Model of Dees and Rotco for the 600 MeV SC

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    The accelerating frequency of the 600 MeV Synchro-Cyclotron (SC) was modulated by the varying capacity of a rotating condenser ("Rotco", the most delicate component of the SC). A 1/5-scale model, dating from the design-period of the SC, was used to study improvements to the SC RF-system, and also the acceleration of ions, first Helium and, at the time of this picture, Carbon. In the middle of the picture is the case containing the Dees. To the left, at the wide end of the cone, a rotco. Reinhold Hohbach is busy with measurements. See also 7805235 (Annual Report 1978, p.110).

  10. Formation of proton radiation belts in the MeV energy range

    Science.gov (United States)

    Panasiuk, M. I.; Sosnovets, E. N.

    1984-09-01

    Satellite data on the spatial location of intensity peaks of radial profiles (Ljm) of protons in the energy range from 500 keV to 100 MeV near the geomagnetic equator are examined. These data are compared with calculations of Ljm(E), taking into account particle transport under the effect of geomagnetic-field fluctuations (GFF). Calculations and experimental data are shown to agree well for a GFF power spectrum having, along with the principal spectrum component Pm(nu) proportional to nu exp -p (where p is about 2), a dominant spectral component at the frequency nu in the mHz range.

  11. Formation of proton radiation belts in region of energies of several MeV

    Science.gov (United States)

    Panasyuk, M. I.; Sosnovets, E. N.

    1985-09-01

    Satellite data on the spatial location of intensity peaks of radial profiles (Ljm) of protons in the energy range from 500 keV to 100 MeV near the geomagnetic equator are examined. These data are compared with calculations of Ljm(E), taking into account particle transport under the effect of geomagnetic-field fluctuations (GFF). Calculations and experimental data are shown to agree well for a GFF power spectrum having, along with the principal spectrum component Pm(nu) proportional to nu exp-p (where p is about 2), a dominant spectral component at the frequency nu in the MHz range.

  12. Spin Dependence in Neutron-Proton Charge Exchange at 790 MeV

    Science.gov (United States)

    Ransome, R. D.; Hollas, C. L.; Riley, P. J.; Bonner, B. E.; Gibbs, W. R.; McNaughton, M. W.; Simmons, J. E.; Bhatia, T. S.; Glass, G.; Hiebert, J. C.; Northcliffe, L. C.; Tippens, W. B.

    1982-03-01

    The analyzing power A and spin-transfer parameters KNN, KSS, KSL, and KLL have been measured in the np charge-exchange (np-->pn) region at 790 MeV. These data provide new and unique information on the spin dependence of the np interaction in the charge-exchange region. Models which explain the charge-exchange peak in the np elastic differential cross section as being due to interference between one-pion exchange and a slowly varying background are in basic agreement with the data.

  13. Modifications induced in the polycarbonate Makrofol KG polymer by Li (50 MeV) ion irradiation

    Indian Academy of Sciences (India)

    Jaskiran Kaur; S K Chakarvarti; D Kanjilal; Surinder Singh

    2009-04-01

    Swift heavy ions interact predominantly through inelastic scattering while traversing any polymer medium and produce excited/ionized atoms. Here samples of the polycarbonate Makrofol of approximate thickness 20 m, spin coated on GaAs substrate were irradiated with 50 MeV Li ion (+3 charge state). Build-in modifications due to irradiation were studied using FTIR and XRD characterizations. Considerable changes have been observed in the polymer while varying the fluence from 1E11 ion/cm2 to 1E13 ion/cm2 Li ions. AFM images of the surface modifications caused by ion irradiation on the polymer are also presented.

  14. Backscattering/transmission of 2 MeV He{sup ++} ions quantitative correlation study

    Energy Technology Data Exchange (ETDEWEB)

    Berec, V., E-mail: bervesn@gmail.com [Institute of Nuclear Sciences Vinca, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia); Germogli, G.; Mazzolari, A.; Guidi, V. [INFN Sezione di Ferrara and Dipartimento di Fisica e Scienze della Terra, Via Saragat 1, 44100 Ferrara (Italy); De Salvador, D. [Dipartimento di Fisica, Università di Padova, Via Marzolo n.8, 35131 Padova (Italy); INFN Laboratori Nazionali di Legnaro, Viale Università 2, 35020 Legnaro, PD (Italy); Bacci, L. [INFN Laboratori Nazionali di Legnaro, Viale Università 2, 35020 Legnaro, PD (Italy)

    2015-07-15

    In this work we report on detailed findings of planar channeling oscillations of 2 MeV He{sup ++} particles in (1 1 0) silicon crystal. The exact correlation and coherence mechanism between confined particles oscillating trajectories are analyzed theoretically and experimentally in backscattering/transmission geometry. Regular patterns of channeled He{sup ++} ion planar oscillations are shown to be dominated by the crystal harmonic-oscillator potential and multiple scattering effect. For the first time it was shown that under the planar channeling conditions trajectories of positively charged particles exhibit observable correlation dynamics, including the interference effect. Quantitative estimation of channeling efficiency is performed using path integral method.

  15. Scale size of magnetic turbulence in tokamaks probed with 30-MeV electrons

    Science.gov (United States)

    Entrop; Lopes Cardozo NJ; Jaspers; Finken

    2000-04-17

    Measurements of synchrotron radiation emitted by 30-MeV runaway electrons in the TEXTOR-94 tokamak show that the runaway population decays after switching on neutral beam injection (NBI). The decay starts only with a significant delay, which decreases with increasing NBI heating power. This delay provides direct evidence of the energy dependence of runaway confinement, which is expected if magnetic modes govern the loss of runaways. Application of the theory by Mynick and Strachan [Phys. Fluids 24, 695 (1981)] yields estimates for the "mode width" (delta) of magnetic perturbations: delta<0.5 cm in Ohmic discharges, increasing to delta = 4.4 cm for 0. 6 MW NBI.

  16. α-clustering effects in dissipative 12C + 12C reactions at 95 MeV

    Science.gov (United States)

    Baiocco, G.; Morelli, L.; Gulminelli, F.; D'Agostino, M.; Bruno, M.; Abbondanno, U.; Barlini, S.; Bini, M.; Carboni, S.; Casini, G.; Cinausero, M.; Degerlier, M.; Gramegna, F.; Kravchuk, V. L.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Raduta, Ad. R.

    2013-05-01

    Dissipative 12C+12C reactions at 95 MeV are fully detected in charge with the GARFIELD and RCo apparatuses at Laboratori Nazionali di Legnaro. A comparison to a dedicated Hauser-Feshbach calculation allows us to select events which correspond, to a large extent, to the statistical evaporation of highly excited 24Mg, as well as to extract information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain. Residual deviations from statistical behavior are observed in α yields and attributed to the persistence of cluster correlations well above the 24Mg threshold for six-α decay.

  17. Measurement of eta photoproduction on the proton from threshold to 1500 MeV

    CERN Document Server

    Bartalini, O; Bocquet, J P; calvat, P; Capogni, M; Casano, L; Castoldi, M; D'Angelo, A; Didelez, J P; Di Salvo, R; Fantini, A; Franco, D; Gaulard, C; Gervino, G; Ghio, F; Giardina, G; Girolami, B; Giusa, A; Guidal, M; Hourany, E; Kunne, Ronald Alexander; Lapik, A; Levi-Sandri, P; Llères, A; Mammoliti, F; Mandaglio, G; Moricciani, D; Mushkarenkov, A N; Nedorezov, V; Nicoletti, L; Perrin, C; Randieri, C; Rebreyend, D; Renard, F; Rudnev, N; Russew, T; Russo, G; Schärf, C; Sperduto, M L; Sutera, M C; Turinge, A; Vegna, V

    2007-01-01

    Beam asymmetry and differential cross section for the reaction gamma+p->eta+p were measured from production threshold to 1500 MeV photon laboratory energy. The two dominant neutral decay modes of the eta meson, eta->2g and eta->3pi0, were analyzed. The full set of measurements is in good agreement with previously published results. Our data were compared with three models. They all fit satisfactorily the results but their respective resonance contributions are quite different. The possible photoexcitation of a narrow state N(1670) was investigated and no evidence was found.

  18. Summary of monoenergetic neutron beam sources for energies gt 14 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Brady, F.P.; Romero, J.L. (Univ. of California-Davis, Crocker Nuclear Lab., Davis, CA (US))

    1990-11-01

    This paper examines the production of neutron beams for energies between {approx}20 and 100 MeV. Considerations for obtaining monoenergetic beams as well as some of the limiting factors, such as energy resolution are examined as well. Production cross sections at 0 deg are reviewed for proton- and deuteron-induced reactions on light elements. Some current facilities in the context of neutron beams obtained by collimation, by the associate particle method, and by the use of a beam swinger are also discussed.

  19. 'Cabinet-safe' study of 1-8 MeV electron accelerators

    CERN Document Server

    Wells, D P; Yoon, W Y; Harmon, F

    2001-01-01

    The development of 'cabinet-safe' accelerator technology for approx 1-8 MeV electron LINACs would remove the only major barrier to large-scale 'field' applications of these accelerators. These applications range from non-destructive evaluation and assay to radiolytic degradation of hazardous waste. All field applications require large forward dose and very little lateral dose. We investigated the origin, energy, and angular distribution of unwanted lateral radiation dose from two different electron LINACS at three energies. We report on the contributions of various beam parameters to unwanted radiation dose and propose methods to control key beam parameters that significantly contribute to these doses.

  20. 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.

  1. GRB observed by IBIS/PICsIT in the MeV energy range

    Energy Technology Data Exchange (ETDEWEB)

    Bianchin, V.; Foschini, L.; Di Cocco, G.; Gianotti, F.; Malaguti, G.; Schiavone, F. [INAF, IASF Bologna, I-40129 Bologna, (Italy); Gotz, D.; Laurent, P. [CEA, IRFU, SAp, F-91191 Gif Sur Yvette, (France); Laurent, P. [APC, F-75205 Paris, (France)

    2009-07-01

    We present the preliminary results of a systematic search for GRB and other transients ill the publicly available data for the IBIS/PICsIT (0.2-10 MeV) detector on board INTEGRAL. Light curves in 2-8 energy bands with time resolution from 1 to 62.5 ms have been collected and an analysis of spectral and temporal characteristics has been performed. This is the nucleus of a forthcoming first catalog of GRB observed by PICsIT. (authors)

  2. Effect of 1.25 MeV gamma irradiation in alpha-phased PVDF

    Energy Technology Data Exchange (ETDEWEB)

    Aarya, Suveda; Siddhartha [Department of Physics, Faculty of Natural Science, Jamia Millia Islamia, New Delhi 110025 (India); Srivastava, A.K. [Department of Applied Science, Ideal Institute of Technology, Govindpuram, Ghaziabad 201003, UP (India); Saha, A. [UGC-DAE Consortium for Scientific Research, Kolkata Center, III/LB-8 Bidhannagar, Kolkata 700098 (India); Wahab, M.A., E-mail: mawahab.physics@gmail.co [Department of Physics, Faculty of Natural Science, Jamia Millia Islamia, New Delhi 110025 (India)

    2009-11-15

    The radiation induced changes taking place in alpha-phased poly(vinylidene fluoride) (PVDF) films exposed to gamma rays were investigated in correlation with the applied doses. Samples were irradiated in vacuum at room temperature by a 1.25 MeV Co{sup 60} source with the doses in the range of 0-300 kGy. Optical and chemical properties of the irradiated as well as un-irradiated PVDF films were studied using UV-visible and FTIR techniques. Gamma irradiation was found to induce changes vary depending on the radiation dose.

  3. Identification of defects in GaAs induced by 1 MeV electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lai, S.T.; Nener, B.D.; Faraone, L.; Nassibian, A.G. [Western Australia Univ., Nedlands, WA (Australia); Hotchkis, M.A.C. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    1993-12-31

    This paper shows that 1 MeV electron irradiation on n-type vapor phase epitaxial (VPE) GaAs creates three electron traps E1, E2 and EL6, and results in the splitting of the EL2 center into two levels EL2-A and EL2-B. A 15 minutes isochronal anneal results in the annihilation of the E1 and E2 traps, a reduction in EL6 trap concentration, and the return of EL2 to a single level EL2-A. A defect model is outlined which correlates with the observed results. 4 refs., 2 tabs., 3 figs.

  4. Nuclear physics research program at the 30 MeV Karaj cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Noshad, H. E-mail: hnoshad@seai.neda.net.ir; Soheyli, S.; Lamehi-Rachti, M.; Talebi-Taher, A.R.; Aslani, Gh.; Maboudi-Moghaddam, S.; Rahighi, J.; Kakuee, O.R.; Heydari, N

    2002-08-01

    A versatile reaction chamber and its accessories as well as a multiparameter data acquisition system were designed, assembled, and installed in the R and D hall at NRCAM to allow nuclear measurements. The {sup 209}Bi(p,f) and {sup 197}Au(p,f) reaction experiments at E{sub p}=30 MeV were performed. The good agreement between our experimental results as compared with previously published data are presented here to show the reliability of our apparatus. In the case of the bismuth reaction, the fission cross section obtained by using pair spectrometry as well as its associated error have been measured for the first time.

  5. Total reaction cross sections of 50 and 65 MeV pions on nuclei

    Science.gov (United States)

    Meirav, O.; Friedman, E.; Altman, A.; Hanna, M.; Johnson, R. R.; Gill, D. R.

    1987-09-01

    Total reaction cross sections have been measured for 50 and 65 MeV π+/- on C, O, 18O, S, Ca, and Zr. The motivation for this experiment is to obtain cross sections to act as constraints in optical model fits to elastic scattering data. Measurements using the ``poor geometry'' transmission method were made for exceptionally small angles with the aim of improving the accuracy of the extrapolation to zero solid angle. At these small solid angles the muon cone from pion decay contributes significantly and its effects were explicitly included. The accuracies of the elastic correction are evaluated by using error matrix techniques and an additional systematic error is included.

  6. Calculation of nucleon production cross sections for 200 MeV deuterons

    Energy Technology Data Exchange (ETDEWEB)

    Ridikas, D.; Mittig, W.

    1997-12-31

    The differential neutron and proton production cross sections have been investigated for 200 MeV incident deuterons on thin and thick {sup 9}Be, {sup 56}Fe and {sup 238}U targets using the LAHET code system. The examples of the deuteron beam on different target materials are analysed to determine the differences of converting the energy of the beam into the nucleons produced. Both double differential, energy and angle integrated nuclear production cross sections are presented together with the average nucleon multiplicities per incident deuteron. (K.A.). 31 refs.

  7. Neutron-proton charge-exchange amplitudes at 585 MeV

    CERN Document Server

    Chiladze, D; Dzyuba, A; Dymov, S; Glagolev, V; Hartmann, M; Kacharava, A; Keshelashvili, I; Khoukaz, A; Komarov, V; Kulessa, P; Kulikov, A; Lomidze, N; Macharashvili, G; Maeda, Y; Mchedlishvili, D; Mersmann, T; Merzliakov, S; Mielke, M; Mikirtychyants, S; Nekipelov, M; Nioradze, M; Ohm, H; Rathmann, F; Ströher, H; Tabidze, M; Trusov, S; Uzikov, Yu; Valdau, Yu; Wilkin, C

    2008-01-01

    The differential cross section and deuteron analysing powers of the dp -> {pp}n charge-exchange reaction have been measured with the ANKE spectrometer at the COSY storage ring. Using a deuteron beam of energy 1170 MeV, data were obtained for small momentum transfers to a {pp} system with low excitation energy. A good quantitative understanding of all the measured observables is provided by the impulse approximation using known neutron-proton amplitudes. The proof of principle achieved here for the method suggests that measurements at higher energies will provide useful information in regions where the existing np database is far less reliable.

  8. Bunch evolution study in optimization of MeV ultrafast electron diffraction

    CERN Document Server

    Lu, Xianhai; Huang, Wenhui; Tang, Chuanxiang

    2014-01-01

    Megaelectronvolt ultrafast electron diffraction (UED) is a promising detection tool for ultrafast processes. The quality of diffraction image is determined by the transverse evolution of the probe bunch. In this paper, we study the contributing terms of the emittance and space charge effects to the bunch evolution in MeV UED scheme, employing a mean-field model with an ellipsoidal distribution as well as particle tracking simulation. Small transverse dimension of the drive laser is found critical to improve the reciprocal resolution, exploiting both smaller emittance and larger transverse bunch size before the solenoid. The degradation of reciprocal spatial resolution caused by the space charge effects should be carefully controlled.

  9. Cross section measurement for (n,n{alpha}) reactions by 14 MeV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Kasugai, Y.; Ikeda, Y.; Uno, Y. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Yamamoto, H.; Kawade, K.

    1997-03-01

    Nine (n,n{alpha}) cross sections for (n,n{alpha}) reactions induced by 13.5-14.9 MeV neutrons were measured for {sup 51}V, {sup 65}Cu, {sup 71}Ga, {sup 76}Ge, {sup 87}Rb, {sup 91}Zr, {sup 93}Nb, {sup 96}Zr and {sup 109}Ag isotopes by using Fusion Neutronics Source (FNS) at JAERI. The reactions for 91Zr and 96Zr were measured for the first time. The evaluated data of JENDL-3 and ENDF/B-VI were compared with the present data. Some of the evaluated values are much different from our data by a factor more than ten. (author)

  10. The cosmic MeV neutrino background as a laboratory for black hole formation

    Directory of Open Access Journals (Sweden)

    Hasan Yüksel

    2015-12-01

    Full Text Available Calculations of the cosmic rate of core collapses, and the associated neutrino flux, commonly assume that a fixed fraction of massive stars collapse to black holes. We argue that recent results suggest that this fraction instead increases with redshift. With relatively more stars vanishing as “unnovae” in the distant universe, the detectability of the cosmic MeV neutrino background is improved due to their hotter neutrino spectrum, and expectations for supernova surveys are reduced. We conclude that neutrino detectors, after the flux from normal SNe is isolated via either improved modeling or the next Galactic SN, can probe the conditions and history of black hole formation.

  11. Production of highly-polarized positrons using polarized electrons at MeV energies

    CERN Document Server

    Abbott, D; Adeyemi, A; Aguilera, P; Ali, M; Areti, H; Baylac, M; Benesch, J; Bosson, G; Cade, B; Camsonne, A; Cardman, L S; Clark, J; Cole, P; Covert, S; Cuevas, C; Dadoun, O; Dale, D; Dong, H; Dumas, J; Fanchini, E; Forest, T; Forman, E; Freyberger, A; Froidefond, E; Golge, S; Grames, J; Guèye, P; Hansknecht, J; Harrell, P; Hoskins, J; Hyde, C; Josey, B; Kazimi, R; Kim, Y; Machie, D; Mahoney, K; Mammei, R; Marton, M; McCarter, J; McCaughan, M; McHugh, M; McNulty, D; Mesick, K E; Michaelides, T; Michaels, R; Moffit, B; Moser, D; Camacho, C Muñoz; Muraz, J -F; Opper, A; Poelker, M; Réal, J -S; Richardson, L; Setiniyaz, S; Stutzman, M; Suleiman, R; Tennant, C; Tsai, C; Turner, D; Ungaro, M; Variola, A; Voutier, E; Wang, Y; Zhang, Y

    2016-01-01

    The Polarized Electrons for Polarized Positrons experiment at the injector of the Continuous Electron Beam Accelerator Facility has demonstrated for the first time the efficient transfer of polarization from electrons to positrons produced by the polarized bremsstrahlung radiation induced by a polarized electron beam in a high-$Z$ target. Positron polarization up to 82\\% have been measured for an initial electron beam momentum of 8.19~MeV/$c$, limited only by the electron beam polarization. This technique extends polarized positron capabilities from GeV to MeV electron beams, and opens access to polarized positron beam physics to a wide community.

  12. Neutron-induced deuteron breakup cross section at 10. 3 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, M.; Bodek, K.; Krug, J.; Lubcke, W.; Obermanns, S.; Ruhl, H.; Steinke, M.; Kamke, D.; Witala, H.; Cornelius, T.; and others

    1989-06-01

    The absolute cross section of /ital n/+/ital d//r arrow//ital n/+/ital n/+/ital p/ at 10.3 MeV incidentneutron energy has been measured in the so called ''space-star'' configuration.The results are compared with three-nucleon calculations based on the Parispotential and the new Bonn potential. The agreement within the experimentaluncertainties of 8% puts an upper limit to the combined corrections due torelativistic effects, on-shell two-nucleon uncertainties, and the three-nucleonforce.

  13. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    CERN Document Server

    Alba, R; Boccaccio, P; Celentano, A; Colonna, N; Cosentino, G; Del Zoppo, A; Di Pietro, A; Esposito, J; Figuera, P; Finocchiaro, P; Kostyukov, A; Maiolino, C; Osipenko, M; Ricco, G; Ripani, M; Viberti, C M; Santonocito, D; Schillaci, M

    2012-01-01

    In the framework of research on IVth generation reactors and high intensity neutron sources a low-power prototype neutron amplifier was recently proposed by INFN. It is based on a low-energy, high current proton cyclotron, whose beam, impinging on a thick Beryllium converter, produces a fast neutron spectrum. The world database on the neutron yield from thick Beryllium target in the 70 MeV proton energy domain is rather scarce. The new measurement was performed at LNS, covering a wide angular range from 0 to 150 degrees and an almost complete neutron energy interval. In this contribution the preliminary data are discussed together with the proposed ADS facility.

  14. \\alpha-clustering effects in dissipative 12C+12C reactions at 95 MeV

    CERN Document Server

    Baiocco, G; Gulminelli, F; D'Agostino, M; Bruno, M; Abbondanno, U; Barlini, S; Bini, M; Carboni, S; Casini, G; Cinausero, M; Gramegna, M Degerlier F; Kravchuk, V L; Marchi, T; Olmi, A; Pasquali, G; Piantelli, S; Raduta, Ad R

    2013-01-01

    Dissipative 12C+12C reactions at 95 MeV are fully detected in charge with the GARFIELD and RCo apparatuses at LNL. A comparison to a dedicated Hauser-Feshbach calculation allows to select events which correspond, to a large extent, to the statistical evaporation of highly excited 24Mg, as well as to extract information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain. Residual deviations from a statistical behaviour are observed in \\alpha yields and attributed to the persistence of cluster correlations well above the 24Mg threshold for 6 \\alpha's decay.

  15. ElectroOptical measurements of ultrashort 45 MeV electron beam bunch

    CERN Document Server

    Nikas, D; Kowalski, L A; Larsen, R; Lazarus, D M; Ozben, C; Semertzidis, Y K; Tsang, Thomas; Srinivasan-Rao, T

    2001-01-01

    We have made an observation of 45 MeV electron beam bunches using the nondestructive electro-optical (EO) technique. The amplitude of the EO modulation was found to increase linearly with electron beam charge and decrease inversely with the optical beam path distance from the electron beam. The risetime of the signal was bandwidth limited by our detection system to \\~70ps. An EO signal due to ionization caused by the electrons traversing the EO crystal was also observed. The EO technique may be ideal for the measurement of bunch structure with femtosecond resolution of relativistic charged particle beam bunches.

  16. Technical preparations for the in-vessel 14 MeV neutron calibration at JET

    Energy Technology Data Exchange (ETDEWEB)

    Batistoni, P., E-mail: paola.batistoni@enea.it [ENEA, Department of Fusion and Nuclear Safety Technology, I-00044, Frascati, Rome (Italy); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Popovichev, S. [CCFE, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Crowe, R. [Remote Applications in Challenging Environments (RACE), Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Cufar, A. [Reactor Physics Division, Jožef Stefan Institute, Jamova cesta 39, SI-1000, Ljubljana (Slovenia); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Ghani, Z. [CCFE, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Keogh, K. [Remote Applications in Challenging Environments (RACE), Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Peacock, A. [JET Exploitation Unit, Abingdon, Oxon, OX14 3DB (United Kingdom); Price, R. [Remote Applications in Challenging Environments (RACE), Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); EUROfusion Consortium, Culham Science Centre, Abingdon, Oxon, OX14 3DB (United Kingdom); Baranov, A.; Korotkov, S.; Lykin, P.; Samoshin, A. [All-Russia Research Institute of Automatics (VNIIA), 22, Sushchevskaya str., 127055, Moscow (Russian Federation)

    2017-04-15

    Highlights: • The JET 14 MeV neutron calibration requires a neutron generator to be deployed inside the vacuum vessel by means of the remote handling system. • A neutron generator of suitable intensity and compliant with physics, remote handling and safety requirements has been identified and procured.The scientific programme of the preparatory phase devoted to fully characterizing the selected 14 MeV neutron generator is discussed. • The aim is to measure the absolute neutron emission rate within (± 5%) and the energy spectrum of emitted neutron as a function of angles. • The physics preparations, source issues, safety and engineering aspects required to calibrate directly the JET neutron detectors are discussed. - Abstract: The power output of fusion devices is measured from their neutron yields which relate directly to the fusion yield. In this paper we describe the devices and methods that have been prepared to perform a new in situ 14 MeV neutron calibration at JET in view of the new DT campaign planned at JET in the next years. The target accuracy of this calibration is ±10% as required for ITER, where a precise neutron yield measurement is important, e.g., for tritium accountancy. In this paper, the constraints and early decisions which defined the main calibration approach are discussed, e.g., the choice of 14 MeV neutron source and the deployment method. The physics preparations, source issues, safety and engineering aspects required to calibrate directly the JET neutron detectors are also discussed. The existing JET remote-handling system will be used to deploy the neutron source inside the JET vessel. For this purpose, compatible tooling and systems necessary to ensure safe and efficient deployment have been developed. The scientific programme of the preparatory phase is devoted to fully characterizing the selected 14 MeV neutron generator to be used as the calibrating source, obtain a better understanding of the limitations of the

  17. TANGRA-Setup for the Investigation of Nuclear Fission Induced by 14.1 MeV Neutrons

    Science.gov (United States)

    Ruskov, I. N.; Kopatch, Yu. N.; Bystritsky, V. M.; Skoy, V. R.; Shvetsov, V. N.; Hambsch, F.-J.; Oberstedt, S.; Noy, R. Capote; Sedyshev, P. V.; Grozdanov, D. N.; Ivanov, I. Zh.; Aleksakhin, V. Yu.; Bogolubov, E. P.; Barmakov, Yu. N.; Khabarov, S. V.; Krasnoperov, A. V.; Krylov, A. R.; Obhođaš, J.; Pikelner, L. B.; Rapatskiy, V. L.; Rogachev, A. V.; Rogov, Yu. N.; Ryzhkov, V. I.; Sadovsky, A. B.; Salmin, R. A.; Sapozhnikov, M. G.; Slepnev, V. M.; Sudac, D.; Tarasov, O. G.; Valković, V.; Yurkov, D. I.; Zamyatin, N. I.; Zeynalov, Sh. S.; Zontikov, A. O.; Zubarev, E. V.

    The new experimental setup TANGRA (Tagged Neutrons & Gamma Rays), for the investigation of neutron induced nuclear reactions, e.g. (n,xn'), (n,xn'γ), (n,γ), (n,f), on a number of important isotopes for nuclear science and engineering (235,238U, 237Np, 239Pu, 244,245,248Cm) is under construction and being tested at the Frank Laboratory of Neutron Physics (FLNP) of the Joint Institute for Nuclear Research (JINR) in Dubna. The TANGRA setup consists of: a portable neutron generator ING-27, with a 64-pixel Si charge-particle detector incorporated into its vacuum chamber for registering of α-particles formed in the T(d, n)4He reaction, as a source of 14.1 MeV steady-state neutrons radiation with an intensity of ∼5x107n/s; a combined iron (Fe), borated polyethylene (BPE) and lead (Pb) compact shielding-collimator; a reconfigurable multi-detector (neutron plus gamma ray detecting system); a fast computer with 2 (x16 channels) PCI-E 100 MHz ADC cards for data acquisition and hard disk storage; Linux ROOT data acquisition, visualization and analysis software. The signals from the α-particle detector are used to 'tag' the neutrons with the coincident α-particles. Counting the coincidences between the α-particle and the reaction-product detectors in a 20ns time-interval improves the effect/background-ratio by a factor of ∼200 as well as the accuracy in the neutron flux determination, which decreases noticeably the overall experimental data uncertainty.

  18. Computer Engineers.

    Science.gov (United States)

    Moncarz, Roger

    2000-01-01

    Looks at computer engineers and describes their job, employment outlook, earnings, and training and qualifications. Provides a list of resources related to computer engineering careers and the computer industry. (JOW)

  19. Measurement of the (236)U(n,f) cross section from 170 MeV to 2 MeV at the CERN n_TOF Facility

    Energy Technology Data Exchange (ETDEWEB)

    Sarmento, R. [Instituto Tecnologico e Nuclear, Sacavem, Portugal; Goncalves, I. F. [Instituto Tecnologico e Nuclear, Sacavem, Portugal; Vaz, P. [Instituto Tecnologico e Nuclear (ITN), Lisbon, Portugal; Carrapico, C. [Instituto Tecnologico e Nuclear (ITN), Lisbon, Portugal; Carrillo de Albornoz, A. [Instituto Tecnologico e Nuclear, Sacavem, Portugal; Marques, L. [Instituto Tecnologico e Nuclear, Sacavem, Portugal; Salgado, J. [Instituto Tecnologico e Nuclear, Sacavem, Portugal; Tavora, L. [Instituto Tecnologico e Nuclear, Sacavem, Portugal; Calviani, M. [CERN, Geneva, Switzerland; Andriamonje, S. [CERN, Geneva, Switzerland; Chiaveri, E. [CERN, Geneva, Switzerland; Guerrero, C. [CERN, Geneva, Switzerland; Vlachoudis, V. [CERN, Geneva, Switzerland; Colonna, N. [Instituto Nazionale di Fisica Nucleare, Bari, Italy; Barbagallo, M. [Instituto Nazionale di Fisica Nucleare, Bari, Italy; Marrone, S. [Instituto Nazionale di Fisica Nucleare, Bari, Italy; Tagliente, G. [Instituto Nazionale di Fisica Nucleare, Bari, Italy; Terlizzi, R. [Instituto Nazionale di Fisica Nucleare, Bari, Italy; Belloni, F. [Instituto Nazionale de Fisica Nucleare, Trieste, Italy; Fuji, K. [Instituto Nazionale de Fisica Nucleare, Trieste, Italy; Milazzo, P. M. [Instituto Nazionale de Fisica Nucleare, Trieste, Italy; Moreau, C. [Instituto Nazionale de Fisica Nucleare, Trieste, Italy; Alvarez-Velarde, F. [Centro de Investigaciones Energeticas Medioambientales y Technol., Madrid, Spain; Cano-Ott, D. [CIEMAT, Madrid; Gonzalez-Romero, E. [CIEMAT, Madrid; Guerrero, C. [Centro de Investigaciones Energeticas Medioambientales y Technol., Madrid, Spain; Martinez, T. [Centro de Investigaciones Energeticas Medioambientales y Technol., Madrid, Spain; Mendoza, E. [Centro de Investigaciones Energeticas Medioambientales y Technol., Madrid, Spain; Villamarin, D. [Centro de Investigaciones Energeticas Medioambientales y Technol., Madrid, Spain; Vicente, M. C. [Centro de Investigaciones Energeticas Medioambientales y Technol., Madrid, Spain; Andrzejewski, Jozef [ORNL; Karamanis, D. [University of Ioannina, Greece; Marganiec, J. [University of Lodz; Assimakopoulos, P. A. [University of Ioannina, Greece; Karadimos, D. [University of Ioannina, Greece; Papachristodoulou, C. [University of Ioannina, Greece; Patronis, N. [University of Ioannina, Greece; Audouin, L. [Universite Paris XI, Orsay, France; David, S. [CNRS, Orsay, France; Ferrant, L. [Universite Paris XI, Orsay, France; Isaev, S. [CNRS/IN2P3, Orsay, France; Stephan, C. [CNRS/IN2P3, Orsay, France; Tassan-Got, L. [CNRS/IN2P3, Orsay, France; Badurek, G. [Vienna University of Technology, Austria; Jericha, E. [Vienna University of Technology, Austria; Leeb, H. [Vienna University of Technology, Austria; Oberhummer, H. [Vienna University of Technology, Austria; Pigni, M. T. [Vienna University of Technology, Austria; Baumann, P. [CNRS, Strasbourg, France; Kerveno, M. [CNRS, Strasbourg, France; Lukic, S. [CNRS, Strasbourg, France; Rudolf, G. [CNRS, Strasbourg, France; Becvar, F. [Charles University, Prague, Czech Republic; Krticka, M. [Charles University, Prague, Czech Republic; Calvino, F. [Universidad Politecnica de Madrid, Spain; Capote, R. [International Atomic Energy Agency (IAEA); Frais-Koelbl, H. [International Atomic Energy Agency (IAEA); Griesmayer, E. [International Atomic Energy Agency (IAEA); Mengoni, A. [International Atomic Energy Agency (IAEA); Praena, J. [University of Seville; Capote, R. [University of Seville; Lozano, M. [University of Seville; Quesada, J. [University of Seville; Cennini (et al.), P. [INFN, Laboratori Nazionali di Legnaro, Italy; Chapel, V. [University of Ciombra, Portugal; Ferreira-Marques, R. [University of Ciombra, Portugal; Lindote, A. [University of Ciombra, Portugal; Lopes, I. [University of Ciombra, Portugal; Neves, F. [University of Ciombra, Portugal; et al.

    2011-01-01

    The neutron-induced fission cross section of {sup 236}U was measured at the neutron Time-of-Flight (n-TOF) facility at CERN relative to the standard {sup 235}U(n,f) cross section for neutron energies ranging from above thermal to several MeV. The measurement, covering the full range simultaneously, was performed with a fast ionization chamber, taking advantage of the high resolution of the n-TOF spectrometer. The n-TOF results confirm that the first resonance at 5.45 eV is largely overestimated in some nuclear data libraries. The resonance triplet around 1.2 keV was measured with high resolution and resonance parameters were determined with good accuracy. Resonances at high energy have also been observed and characterized and different values for the cross section are provided for the region between 10 keV and the fission threshold. The present work indicates various shortcomings of the current nuclear data libraries in the subthreshold region and provides the basis for an accurate re-evaluation of the {sup 236}U(n,f) cross section, which is of great relevance for the development of emerging or innovative nuclear reactor technologies.

  20. Computer Music

    Science.gov (United States)

    Cook, Perry R.

    This chapter covers algorithms, technologies, computer languages, and systems for computer music. Computer music involves the application of computers and other digital/electronic technologies to music composition, performance, theory, history, and the study of perception. The field combines digital signal processing, computational algorithms, computer languages, hardware and software systems, acoustics, psychoacoustics (low-level perception of sounds from the raw acoustic signal), and music cognition (higher-level perception of musical style, form, emotion, etc.).

  1. Detectable MeV neutrinos from black hole neutrino-dominated accretion flows

    CERN Document Server

    Liu, Tong; Ma, Ren-Yi; Xue, Li

    2015-01-01

    Neutrino-dominated accretion flows (NDAFs) around rotating stellar-mass black holes (BHs) have been theorized as the central engine of relativistic jets launched in massive star core collapse events or compact star mergers. In this work, we calculate the electron neutrino/anti-neutrino spectra of NDAFs by fully taking into account the general relativistic effects, and investigate the effects of viewing angle, BH spin, and mass accretion rate on the results. We show that even though a typical NDAF has a neutrino luminosity lower than that of a typical supernova, it can reach $10^{50}-10^{51}~{\\rm erg~s^{-1}}$ peaking at $\\sim 10$ MeV, making them potentially detectable with the upcoming sensitive MeV neutrino detectors if they are close enough to Earth. Based on the event rate of NDAFs in the local universe, we estimate a detection rate up to $\\sim$ 5 per century by the Hyper-Kamiokande detector. Detecting one such event would establish the observational evidence of NDAFs in the universe.

  2. Detectable MeV neutrinos from black hole neutrino-dominated accretion flows

    Science.gov (United States)

    Liu, Tong; Zhang, Bing; Li, Ye; Ma, Ren-Yi; Xue, Li

    2016-06-01

    Neutrino-dominated accretion flows (NDAFs) around rotating stellar-mass black holes (BHs) have been theorized as the central engine of relativistic jets launched in massive star core collapse events or compact star mergers. In this work, we calculate the electron neutrino/antineutrino spectra of NDAFs by fully taking into account the general relativistic effects, and investigate the effects of viewing angle, BH spin, and mass accretion rate on the results. We show that even though a typical NDAF has a neutrino luminosity lower than that of a typical supernova (SN), it can reach 1050- 1051 erg s-1 peaking at ˜10 MeV , making NDAFs potentially detectable with the upcoming sensitive MeV neutrino detectors if they are close enough to Earth. Based on the observed gamma-ray burst (GRB) event rate in the local universe and requiring that at least three neutrinos are detected to claim a detection, we estimate a detection rate up to ˜(0.10 - 0.25 ) per century for GRB-related NDAFs by the Hyper-Kamiokande (Hyper-K) detector if one neglects neutrino oscillation. If one assumes that all type Ib/c SNe have an engine-driven NDAF, the Hyper-K detection rate would be ˜(1 - 3 ) per century. By considering neutrino oscillations, the detection rate may decrease by a factor of 2-3. Detecting one such event would establish the observational evidence of NDAFs in the Universe.

  3. Neutron-deuteron analyzing power data at En=22.5 MeV

    Science.gov (United States)

    Weisel, G. J.; Tornow, W.; Crowell, A. S.; Esterline, J. H.; Hale, G. M.; Howell, C. R.; O'Malley, P. D.; Tompkins, J. R.; Witała, H.

    2014-05-01

    We present measurements of n-d analyzing power, Ay(θ), at En=22.5 MeV. The experiment uses a shielded neutron source which produced polarized neutrons via the 2H(d⃗,n⃗)3He reaction. It also uses a deuterated liquid-scintillator center detector and six pairs of liquid-scintillator neutron side detectors. Elastic neutron scattering events are identified by using time-of-flight techniques and by setting a window in the center detector pulse-height spectrum. The beam polarization is monitored by using a high-pressure helium gas cell and an additional pair of liquid-scintillator side detectors. The n-d Ay(θ) data were corrected for finite-geometry and multiple-scattering effects using a Monte Carlo simulation of the experiment. The 22.5-MeV data demonstrate that the three-nucleon analyzing power puzzle also exists at this energy. They show a significant discrepancy with predictions of high-precision nucleon-nucleon potentials alone or combined with Tucscon-Melbourne or Urbana IX three-nucleon forces, as well as currently available effective-field theory based potentials of next-to-next-to-next-to-leading order.

  4. Technology for Fissionable Materials Detection by Use of 100 MeV Variable Linac

    CERN Document Server

    Karasyov, Sergey P; Dovbnja, Anatoliy N; Eran, L; Kiryukhin, Nikolay M; Melnik, Yu M; Ran'iuk, Yu; Shlyakhov, Il'ya N; Trubnikov, Sergiy V

    2005-01-01

    A new concept for a two-step facility to increase the accuracy/reliability of detecting heavily shielded fissionable materials (FM) in marine containers is presented. The facility will detect FM in two steps. An existing dual-view; dual-energy X-ray scanner, which is based on 7 MeV electron accelerator, will select the suspicious places inside container. The linac with variable energy (up to 100 MeV) will be used for the second step. The technology will detect fissionable nuclei by gamma induced fission reactions and delayed neutron registration. A little-known Ukrainian experimental data obtained in Chernobil' clean-up program will be presented to ground proposed concept. The theoretical calculations of neutron fluxes scale these results to marine container size. Modified GEANT code for electron/gamma penetration and authors' own software for neutron yield/penetration are used for these calculations. Available facilities (X-ray scanners; linac; detectors), which will be used for concept proof, are described....

  5. The Angular Distribution of Neutrons Scattered from Deuterium below 2 MeV

    Science.gov (United States)

    Nankov, N.; Plompen, A. J. M.; Kopecky, S.; Kozier, K. S.; Roubtsov, D.; Rao, R.; Beyer, R.; Grosse, E.; Hannaske, R.; Junghans, A. R.; Massarczyk, R.; Schwengner, R.; Yakorev, D.; Wagner, A.; Stanoiu, M.; Canton, L.; Nolte, R.; Röttger, S.; Beyer, J.; Svenne, J.

    2014-05-01

    Neutron elastic scattering measurements were carried out at the nELBE neutron time-of-flight facility at a 6 m flight path. Energies below 2 MeV were studied using a setup consisting of eight 6Li-glass detectors placed at nominal angles of 15∘ and 165∘ with respect to the incident neutron beam. A deuterated polyethylene sample with 99.999% enrichment in deuterium was used. These angles were chosen since an earlier study showed that the ratio of the differential cross section at these angles is the most sensitive to differences in evaluated files and model calculations. Accurate 165∘/15∘ angle ratios were obtained. Above 1 MeV these are somewhat larger than given by ENDF/B-VII. Simultaneously the early day experiments using a proportional counter to infer angular distributions from deuterium recoil pulse height distributions are being studied through a new experiment with such a device at the Physikalisch-Technische Bundesanstalt (PTB). At 500 keV this experiment favors ENDF/B-VII over JENDL-4.0, while at lower energies agreement with the data is similar.

  6. Production of α-particle emitting 211At using 45 MeV α-beam

    Science.gov (United States)

    Kim, Gyehong; Chun, Kwonsoo; Park, Sung Ho; Kim, Byungil

    2014-06-01

    Among the α-particle emitting radionuclides, 211At is considered to be a promising radionuclide for targeted cancer therapy due to its decay properties. The range of alpha particles produced by the decay of 211At are less than 70 µm in water with a linear energy transfer between 100 and 130 keV µm-1, which are about the maximum relative biological effectiveness for heavy ions. It is important to note that at the present time, only a few of cyclotrons routinely produce 211At. The direct production method is based on the nuclear reactions 209Bi(α,2n)211At. Production of the radionuclide 211At was carried out using the MC-50 cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS). To ensure high beam current, the α-beam was extracted with an initial energy of 45 MeV, which was degraded to obtain the appropriate α-beam energy. The calculations of beam energy degradation were performed utilizing the MCNPX. Alumina-baked targets were prepared by heating the bismuth metal powder onto a circular cavity in a furnace. When using an Eα, av of 29.17 MeV, the very small contribution of 210At confirms the right choice of the irradiation energy to obtain a pure production of 211At isotope.

  7. A gas ionisation Direct-STIM detector for MeV ion microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Norarat, Rattanaporn, E-mail: rattanaporn@rmutl.ac.th [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Faculty of Science and Agriculture, Rajamangala University of Technology Lanna, Chiang Rai, 57120 Chiang Rai (Thailand); Department of Physics, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014 (Finland); Guibert, Edouard; Jeanneret, Patrick; Dellea, Mario; Jenni, Josef [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Roux, Adrien; Stoppini, Luc [Tissue Engineering Laboratory, Campus Biotech, Chemin des Mines 9, Geneva (Switzerland); Whitlow, Harry J. [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland)

    2015-04-01

    Direct-Scanning Transmission Ion Microscopy (Direct-STIM) is a powerful technique that yields structural information in sub-cellular whole cell imaging. Usually, a Si p-i-n diode is used in Direct-STIM measurements as a detector. In order to overcome the detrimental effects of radiation damage which appears as a broadening in the energy resolution, we have developed a gas ionisation detector for use with a focused ion beam. The design is based on the ETH Frisch grid-less off-axis Geiger–Müller geometry. It is developed for use in a MeV ion microscope with a standard Oxford Microbeams triplet lens and scanning system. The design has a large available solid angle for other detectors (e.g. proton induced fluorescence). Here we report the performance for imaging ReNcells VM with μm resolution where energy resolutions of <24 keV fwhm could be achieved for 1 MeV protons using isobutane gas.

  8. Validation of the Geant4 simulation of bremsstrahlung from thick targets below 3 MeV

    CERN Document Server

    Pandola, Luciano; Caccia, Barbara

    2014-01-01

    The bremsstrahlung spectra produced by electrons impinging on thick targets are simulated using the Geant4 Monte Carlo toolkit. Simulations are validated against experimental data available in literature for a range of energy between 0.5 and 2.8 MeV for Al and Fe targets and for a value of energy of 70 keV for Al, Ag, W and Pb targets. All three independent sets of electromagnetic models available in Geant4 to simulate bremsstrahlung are tested. A quantitative analysis is performed reproducing with each model the energy spectrum for the different configurations of emission angles, energies and targets. At higher energies (0.5-2.8 MeV) of the impinging electrons on Al and Fe targets, Geant4 is able to reproduce the spectral shapes and the integral photon emission in the forward direction (at better than 10%). The physics model based on the Penelope Monte Carlo code seems slightly preferable over the other two. However, all models over-estimate the photon emission in the backward hemisphere. For the lower energ...

  9. Response of diamond detector sandwich to 14 MeV neutrons

    CERN Document Server

    Osipenko, M; Ricco, G; Caiffi, B; Pompili, F; Pillon, M; Verona-Rinati, G; Cardarelli, R

    2015-01-01

    In this paper we present the measurement of the response of 50 $\\mu$m thin diamond detectors to 14 MeV neutrons. Such neutrons are produced in fusion reactors and are of particular interest for ITER neutron diagnostics. Among semiconductor detectors diamond has properties most appropriate for harsh radiation and temperature conditions of a fusion reactor. However, 300-500 $\\mu$m thick diamond detectors suffer significant radiation damage already at neutron fluences of the order of $10^{14}$ n/cm$^2$. It is expected that a 50 $\\mu$m thick diamond will withstand a fluence of $>10^{16}$ n/cm$^2$. We tested two 50 $\\mu$m thick single crystal CVD diamonds, stacked to form a ``sandwich'' detector for coincidence measurements. The detector measured the conversion of 14 MeV neutrons, impinging on one diamond, into $\\alpha$ particles which were detected in the second diamond in coincidence with nuclear recoil. For $^{12}C(n,\\alpha)^{9}Be$ reaction the total energy deposited in the detector gives access to the initial ...

  10. Commissioning of the Linac4 RFQ at the 3 MeV test stand

    CERN Document Server

    Rossi, C; Bellodi, G; Broere, J; Brunner, O; Lombardi, A M; Balula, J M; Yanez, P M; Noirjean, J; Pasquino, C; Raich, U; Roncarolo, F; Vretenar, M; Desmons, M; France, A; Piquet, O

    2013-01-01

    Linac4, the future 160 MeV Hˉ injector to the CERN Proton Synchrotron Booster, is presently under construction at CERN as a first step of the planned upgrade of the LHC injectors. The low energy section of LINAC4, consisting of an ion source, a 352.2 MHz Radio Frequency Quadrupole (RFQ) and a chopper line is being commissioned in a dedicated test stand before installation in its final position in the tunnel. The RFQ is designed to accelerate a 45 keV, 70 mA, Hˉ beam to 3 MeV, with an efficiency of 95% while preserving the transverse emittance. The RFQ, a four-vane structure 3 m in length, has been designed in collaboration with CEA/IRFU and is has been fabricated at the CERN workshop. The precise fabrication has allowed achieving a field flatness of 1%. The completion of the accelerating structure in September 2012 was followed by a complete series of bead-pull measurements and by high-power conditioning to the nominal power of 0.39 MW corresponding to a voltage of 78 kV across the 3 meters. Measurements wi...

  11. Depicting the MeV realm with the Compton Pair-Production Telescope (ComPair)

    Science.gov (United States)

    Ferrara, Elizabeth C.; Buson, Sara; ComPair Mission Team

    2017-01-01

    The energy band from a few hundred keV to a few hundred MeV offers a unique window for studying both thermal and the non-thermal astrophysical processes. Important science can be gleaned from investigations of emission mechanisms and environments of the most extreme objects that populate this mostly unexplored energy range.The Compton-Pair Telescope (ComPair) is a next-generation mission concept building on the pioneering observations by COMPTEL, on the Compton Gamma-Ray Observatory, and the heritage of recent successful missions, such as Fermi-LAT, AGILE, AMS and PAMELA. With its capability of detecting both Compton-scattering events at lower energy and pair-production events at higher energy, ComPair can explore the energy regime from 0.2 keV to > 500 MeV with unprecedented sensitivity. We describe the concept of this wide-aperture instrument and discuss its power to address fundamental questions from a broad variety of astrophysical topics.

  12. Defect creation by MeV clusters in LiNbO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Canut, B. [Universite Claude Bernard, Villeurbanne (France). Dept. de Phys. des Mater.; Ramos, S. [Universite Claude Bernard, Villeurbanne (France). Dept. de Phys. des Mater.; Bonardi, N. [Universite Claude Bernard, Villeurbanne (France). Dept. de Phys. des Mater.; Chaumont, J. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, CNRS IN2P3, 91405 Orsay Campus (France); Bernas, H. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, CNRS IN2P3, 91405 Orsay Campus (France); Cottereau, E. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, CNRS IN2P3, 91405 Orsay Campus (France)

    1997-02-01

    Single crystals of LiNbO{sub 3} (Y-cut orientation) were irradiated at room temperature with 3 MeV C{sub 6}{sup +} and 2.4 MeV C{sub 8}{sup +} clusters provided by CSNSM ``ARAMIS`` accelerator. The electronic stopping power was about 6.5 keV nm{sup -1} in both cases. The fluences extended from 10{sup 10} to 4 x 10{sup 12} C{sub 6}{sup +} or C{sub 8}{sup +}cm{sup -2}. Rutherford backscattering spectrometry in channeling geometry (RBS/C) revealed the presence of extended defects, which cannot be due solely to nuclear stopping and which we ascribe to the high density of electronic energy associated with the correlated electronic stopping of the cluster components. The RBS/C analysis, providing a lattice disorder profile, confirms this interpretation: the damaged thickness closely corresponds to the cluster components correlation length (between 50 and 100 nm). The fluence evolutions of the disorder ratio, measured at the sample surface for C{sub 6} and C{sub 8} projectiles, correspond to damage cross sections close to 1.8 x 10{sup -13} cm{sup 2} in the two cases. (orig.).

  13. GAMMA-LIGHT: High-Energy Astrophysics above 10 MeV

    CERN Document Server

    Morselli, Aldo; Barbiellini, Guido; Bonvicini, Walter; Bulgarelli, Andrea; Cardillo, Martina; Chen, Andrew; Coppi, Paolo; Di Giorgio, Anna Maria; Donnarumma, Immacolata; Del Monte, Ettore; Fioretti, Valentina; Galli, Marcello; Giusti, Manuela; Ferrari, Attilio; Fuschino, Fabio; Giommi, Paolo; Giuliani, Andrea; Labanti, Claudio; Lipari, Paolo; Longo, Francesco; Marisaldi, Martino; Molinari, Sergio; Muñoz, Carlos; Neubert, Torsten; Orleanski, Piotr; Paredes, Josep M; Pérez-García, M Ángeles; Piano, Giovanni; Picozza, Piergiorgio; Pilia, Maura; Pittori, Carlotta; Pucella, Gianluca; Sabatini, Sabina; Striani, Edoardo; Tavani, Marco; Trois, Alessio; Vacchi, Andrea; Vercellone, Stefano; Verrecchia, Francesco; Vittorini, Valerio; Zdziarski, Andrzej

    2014-01-01

    High-energy phenomena in the cosmos, and in particular processes leading to the emission of gamma- rays in the energy range 10 MeV - 100 GeV, play a very special role in the understanding of our Universe. This energy range is indeed associated with non-thermal phenomena and challenging particle acceleration processes. The technology involved in detecting gamma-rays is challenging and drives our ability to develop improved instruments for a large variety of applications. GAMMA-LIGHT is a Small Mission which aims at an unprecedented advance of our knowledge in many sectors of astrophysical and Earth studies research. The Mission will open a new observational window in the low-energy gamma-ray range 10-50 MeV, and is configured to make substantial advances compared with the previous and current gamma-ray experiments (AGILE and Fermi). The improvement is based on an exquisite angular resolution achieved by GAMMA-LIGHT using state-of-the-art Silicon technology with innovative data acquisition. GAMMA-LIGHT will add...

  14. Performance of the CERN PSB at 160 MeV with $H^{-}$ charge exchange injection

    CERN Document Server

    AUTHOR|(CDS)2084247; Santoni, Claudio

    As part of the LHC Injectors Upgrade Project, the CERN PS Booster (PSB) will be upgraded with a H- charge exchange injection system and its injection energy will be raised from 50 MeV to 160 MeV to obtain the beam brightness required for the LHC High-Luminosity Upgrade. Space charge effects like beam losses and transverse emittance blow-up at injection are expected to be the main limitations towards the achievement of the required high brightness. Studies of beam dynamics in presence of space charge in order to evaluate the performances of the PSB after the Upgrade have been performed. The first part of the work consists of measurements in the present machine, to study the effects of space charge and its interplay with resonances and to have a good set of data for code benchmarking. The code chosen for the beam tracking in presence of space charge is PTC-Orbit (and PyOrbit). Necessary numerical convergence studies are presented together with a benchmark with the PSB measurements. Once assessed the code and it...

  15. Radiation protection studies for a high-power 160 MeV proton linac

    CERN Document Server

    Mauro, Egidio

    2009-01-01

    CERN is presently designing a new chain of accelerators to replace the present Proton Synchrotron (PS) complex: a 160 MeV room-temperature H− linac (Linac4) to replace the present 50 MeV proton linac injector, a 3.5 GeV Superconducting Proton Linac (SPL) to replace the 1.4 GeV PS Booster (PSB) and a 50 GeV synchrotron (named PS2) to replace the 26 GeV PS. Linac4 has been funded and the civil engineering work started in October 2008, whilst the SPL is in an advanced stage of design. Beyond injecting into the future 50 GeV PS, the ultimate goal of the SPL is to generate a 4 MW beam for the production of intense neutrino beams. The radiation protection design is driven by the latter requirement. This work summarizes the radiation protection studies conducted for Linac4. FLUKA Monte Carlo simulations, complemented by analytical estimates, were performed to evaluate the propagation of neutrons through the waveguide, ventilation and cable ducts placed along the accelerator, to estimate the radiological impact of ...

  16. Diagnostics for a 1.2 kA, 1 MeV, electron induction injector

    Science.gov (United States)

    Houck, T. L.; Anderson, D. E.; Eylon, S.; Henestroza, E.; Lidia, S. M.; Vanecek, D. L.; Westenskow, G. A.; Yu, S. S.

    1998-12-01

    We are constructing a 1.2 kA, 1 MeV, electron induction injector as part of the RTA program, a collaborative effort between LLNL and LBNL to develop relativistic klystrons for Two-Beam Accelerator applications. The RTA injector will also be used in the development of a high-gradient, low-emittance, electron source and beam diagnostics for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility. The electron source will be a 3.5″-diameter, thermionic, flat-surface, m-type cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150 ns flat top (1% energy variation), and a normalized edge emittance of less than 200 π-mm-mr. Precise measurement of the beam parameters is required so that performance of the RTA injector can be confidently scaled to the 4 kA, 3 MeV, and 2-microsecond pulse parameters of the DARHT injector. Planned diagnostics include an isolated cathode with resistive divider for direct measurement of current emission, resistive wall and magnetic probe current monitors for measuring beam current and centroid position, capacitive probes for measuring A-K gap voltage, an energy spectrometer, and a pepperpot emittance diagnostic. Details of the injector, beam line, and diagnostics are presented.

  17. Diagnostics for a 1.2 kA, 1 MeV electron induction injector

    Energy Technology Data Exchange (ETDEWEB)

    Houck, T.L.; Anderson, D.E.; Eylon, S.; Henestroza, E.; Lidia, S.M.; Vanecek, D.L.; Westenskow, G.A.; Yu, S.S.

    1998-05-11

    We are constructing a 1.2-kA, 1-MeV, electron induction injector as part of the RTA program, a collaborative effort between LLNL and LBNL to develop relativistic klystrons for Two-Beam Accelerator applications. The RTA injector will also be used in the development of a high-gradient, low-emittance, electron source and beam diagnostics for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT) Facility. The electron source will be a 3.5``-diameter, thermionic, flat-surface, m-type cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 200 {pi}-mm-mr. Precise measurement of the beam parameters is required so that performance of the RTA injector can be confidently scaled to the 4-kA, 3-MeV, and 2-microsecond pulse parameters of the DARHT injector. Planned diagnostics include an isolated cathode with resistive divider for direct measurement of current emission, resistive wall and magnetic probe current monitors for measuring beam current and centroid position, capacitive probes for measuring A-K gap voltage, an energy spectrometer, and a pepper-pot emittance diagnostic. Details of the injector, beam line, and diagnostics are presented.

  18. $^{12}$C(p,n)$^{12}$N reaction at 135 MeV

    CERN Document Server

    Anderson, B D; Millener, D J; Manley, D M; Baldwin, A R; Fazely, A; Madey, R; Tamimi, N; Watson, J W; Foster, C C

    1996-01-01

    We report observations from the (p,n) reaction on 12C at 135 MeV. The experiment was performed with the beam-swinger neutron time-of-flight system at the Indiana University Cyclotron Facility. Neutrons were detected in large-volume plastic scintillation detectors located in three detector stations at 0 deg, 24 deg, and 45 deg with respect to the undeflected beam line; the flight paths were 91 m, 91 m, and 74 m, respectively. Overall time resolutions of about 825 ps provided energy resolutions of about 350 keV in the first two stations and about 425 keV in the third station. The angular distributions for states with excitation energies up to 10 MeV are presented and comparisons are made with DWIA calculations that use one-body density matrices from 0hw and 1hw shell-model calculations. New information is deduced on the excitation energies, widths and spin-parity assignments for several energy levels of 12N.

  19. Gamma-ray emission from the galactic anticenter at MeV energies

    Energy Technology Data Exchange (ETDEWEB)

    Graser, U.; Schoenfelder, V.

    1982-12-15

    An image of the anticenter region of the Galaxy between right ascension 50/sup 0/ and 110/sup 0/ and between declination +10/sup 0/ and +50/sup 0/ in the energy range 1.1--10 MeV is derived from data obtained during a balloon flight with the MPI Compton telescope. The telescope has a field of view of 40/sup 0/--50/sup 0/ (FWHM) and a 1 sigma angular resolution of about 4/sup 0/ within this field. A significantly enhanced ..gamma..-ray emission is observed along the galactic plane from l/sup II/ = 160/sup 0/ to l/sup II/ = 197/sup 0/. Part of the emission is due to the Crab Nebula. The energy spectrum of the pulsed and total Crab emission is determined. Because of the limited angular resolution of the telescope it is not possible to decide whether the remainder of the emission is diffuse in nature or due to unresolved sources. No significantly enhanced ..gamma..-ray emission is observed from the direction of the high-energy ..gamma..-ray source Geminga (2CG 195+04) or from the Seyfert galaxy MCG 8--11--11, which recently was reported to be a soft ..gamma..-ray source. An upper limit to the diffuse galactic ..gamma..-ray emission is determined, which leads to restrictions of the spectrum of interstellar cosmic ray electrons at MeV energies.

  20. COMPTEL all-sky imaging at 2.2 MeV

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, M.; Ryan, J. [University of New Hampshire, Durham, New Hampshire (United States); Fletcher, S. [Los Alamos National Laboratory, Los Alamos, New Mexico (United States); Bennett, K.; van Dijk, R. [Astrophysics Division, ESTEC, Noordwijk (The Netherlands); Bloemen, H.; Hermsen, W. [SRON-Utrecht, Utrecht (The Netherlands); Diehl, R.; Schoenfelder, V.; Strong, A. [Max Planck Institute (MPE), Garching (Germany)

    1997-05-01

    It is now generally accepted that accretion of matter onto a compact object (white dwarf, neutron star or black hole) is one of the most efficient processes in the universe for producing high energy radiations. Measurements of the {gamma}-ray emission will provide a potentially valuable means for furthering our understanding of the accretion process. Here we focus on neutron capture processes, which can be expected in any situation where energetic neutrons may be produced and where the liberated neutrons will interact with matter before they decay (where they have a chance of undergoing some type of neutron capture). Line emission at 2.2 MeV, resulting from neutron capture on hydrogen, is believed to be the most important neutron capture emission. Observations of this line in particular would provide a probe of neutron production processes (i.e., the energetic particle interactions) within the accretion flow. Here we report on the results of our effort to image the full sky at 2.2 MeV using data from the {ital COMPTEL} experiment on the {ital Compton Gamma-Ray Observatory} ({ital CGRO}). {copyright} {ital 1997 American Institute of Physics.}

  1. A Transformative Imaging Capability Using Laser Driven Multi MeV Photon Sources

    Science.gov (United States)

    Gautier, Donald; Espy, Michelle; Palaniyappan, Sasi; Mendez, Jacob; Nelson, Ronald; Hunter, James; Fernandez, Juan; los alamos national laboratory Team

    2016-10-01

    Recent results from the LANL Trident Laser demonstrate the practical use of a laser of this class ( 70 J, 600 fs) as a multi MeV photon source. The utilization of novel targets operating in the relativistic transparency regime of laser-plasmas has enabled this development. The electron population made from these targets, when coupled to a suitable high-Z converter foil placed near the laser target, produces an intense >1 MeV photon source with a small source size compared to conventional sources. When coupled with efficient imaging detectors, this laser-driven hard x-ray source provides new capabilities to address current non-destructive and dynamic testing problems that require a quantum jump in resolution. ``Flash'' (pulse picosecond) photon imaging, micro-focus resolution enhancement, good object penetration, and magnification (4x) with sufficient dose (>10 Rad/sr) for practical application have all been demonstrated at the LANL Trident Laser, as summarized in this presentation.

  2. Toward 10 meV electron energy-loss spectroscopy resolution for plasmonics.

    Science.gov (United States)

    Bellido, Edson P; Rossouw, David; Botton, Gianluigi A

    2014-06-01

    Energy resolution is one of the most important parameters in electron energy-loss spectroscopy. This is especially true for measurement of surface plasmon resonances, where high-energy resolution is crucial for resolving individual resonance peaks, in particular close to the zero-loss peak. In this work, we improve the energy resolution of electron energy-loss spectra of surface plasmon resonances, acquired with a monochromated beam in a scanning transmission electron microscope, by the use of the Richardson-Lucy deconvolution algorithm. We test the performance of the algorithm in a simulated spectrum and then apply it to experimental energy-loss spectra of a lithographically patterned silver nanorod. By reduction of the point spread function of the spectrum, we are able to identify low-energy surface plasmon peaks in spectra, more localized features, and higher contrast in surface plasmon energy-filtered maps. Thanks to the combination of a monochromated beam and the Richardson-Lucy algorithm, we improve the effective resolution down to 30 meV, and evidence of success up to 10 meV resolution for losses below 1 eV. We also propose, implement, and test two methods to limit the number of iterations in the algorithm. The first method is based on noise measurement and analysis, while in the second we monitor the change of slope in the deconvolved spectrum.

  3. Assessment of Tracers of 1.8 MeV Emission

    CERN Document Server

    Knödlseder, J; Oberlack, U G; Von Ballmoos, P; Blömen, H; Hermsen, W; Iyudin, A; Ryan, J; Schönfelder, V

    1999-01-01

    We examined the question of a possible correlation between 1.8 MeV emission and intensity distributions observed at other wavelengths by comparing the 1.8 MeV data to an extended set of all-sky maps, covering the entire explored wavelength range from the radio band up to high-energy gamma-rays. This analysis revealed that tracers of the old stellar population or the local interstellar medium provide only a poor description of the data. Tracers of the young stellar population considerably improve the fit. Residuals are minimized for the free-free emission map obtained by the DMR at microwave wavelengths and the 158 um fine-structure line map of C+ observed by FIRAS. Within the statistics of the present data, both maps provide an overall satisfactory fit. We therefore conclude that adequate tracers of 26Al sources have now been identified. Implications for 26Al source types are discussed (see also Knodlseder, these proceedings).

  4. Beam tracking simulation in the central region of a 13 MeV PET cyclotron

    Science.gov (United States)

    Anggraita, Pramudita; Santosa, Budi; Taufik, Mulyani, Emy; Diah, Frida Iswinning

    2012-06-01

    This paper reports the trajectories simulation of proton beam in the central region of a 13 MeV PET cyclotron, operating with negative proton beam (for easier beam extraction using a stripper foil), 40 kV peak accelerating dee voltage at fourth harmonic frequency of 77.88 MHz, and average magnetic field of 1.275 T. The central region covers fields of 240mm × 240mm × 30mm size at 1mm resolution. The calculation was also done at finer 0.25mm resolution covering fields of 30mm × 30mm × 4mm size to see the effects of 0.55mm horizontal width of the ion source window and the halted trajectories of positive proton beam. The simulations show up to 7 turns of orbital trajectories, reaching about 1 MeV of beam energy. The distribution of accelerating electric fields and magnetic fields inside the cyclotron were calculated in 3 dimension using Opera3D code and Tosca modules for static magnetic and electric fields. The trajectory simulation was carried out using Scilab 5.3.3 code.

  5. GRH Characterization using 4.4 MeV ^12C Gamma-Rays

    Science.gov (United States)

    Kim, Y.; Herrmann, H. W.; Langenbrunner, J. R.; Young, C. S.; Barton, B. T.; Mack, J. M.; McEvoy, A. M.; Evans, S.; Sedillo, T.; Stoeffl, W.; Horsfield, C. J.; Rubery, M.; Miller, E. K.; Grafil, E.

    2010-11-01

    The OMEGA Gamma Reaction History (GRH) diagnostic has been characterized using a relatively well-known source of 4.43 MeV gamma rays produced from inelastic scattering of DT-neutrons off of a graphite puck placed near an imploding capsule at the OMEGA laser facility. An independently measured neutron yield, combined with the known ^12C density and ^12C(n,n'γ)^12C cross-section, allows an in-situ calibration of the GRH detection efficiency at 4.43 MeV. GRH data were collected at two different ^12C target locations to confirm the published angular distribution of gamma rays and were compared with MCNP modeling predictions. These in-situ calibrations were used to validate the GRH simulation code based on a coupled MCNP/ACCEPT Monte-Carlo method. By combining these results with other absolute calibration methods, we are able to infer a DT branching ratio for gamma to neutron production and to make an accurate plastic ablator areal density measurement.

  6. Beam tests on the 4-kA, 1. 5-MeV injector for FXR

    Energy Technology Data Exchange (ETDEWEB)

    Kulke, B.; Kihara, R.; Ravenscroft, D.; Scarpetti, R.; Vogtlin, G.

    1981-01-01

    The new flash x-ray machine (FXR) at Lawrence Livermore National Laboratory is scheduled for completion in late 1981. This is a 54 module, linear induction accelertor, designed to deliver 500 Roentgen at 1 m as bremsstrahlung from a 20 MeV, 4 kA, 60 ns pulsed electron beam. The 9 cm diameter, cold-cathode electron source generates a 15 kA emitted beam at 1.5 MeV, and collimation is being used to reduce the transmitted current to 3.5 kA, with an emittance of 70 mr-cm. The collimated beam diameter is 4 cm. Six ferrite-loaded cavities are used in tandem to energize the injector. The high voltage performance of the injector cavities and other pulsed-power conditioning elements was tested earlier in a series of 10/sup 5/ shots at 400 kV per cavity. An overview of the injector design and of the beam test results is given.

  7. A study of isospin symmetry breaking in carbon 12 with 50 MeV pions

    Energy Technology Data Exchange (ETDEWEB)

    Applegate, J M

    1993-03-01

    In the first experiment to use the superconducting RF cavity at LAMPF known as the Scruncher, cross sections have been measured for the 1+ doublet in {sup 12}C by 50 MeV {pi}r{sup {plus_minus}} scattering. The cross section ratio of the isoscalar to the isovector states was found to be 6.8 {plus_minus} 1.3 for {pi}{sup +}+ scattering and 3.9 {plus_minus} 1.4 for {pi}{sup {minus}} scattering. These ratios give an isospin mixing matrix element H{sub 01}, of 119 {plus_minus} 40 key, in good agreement with the average value of 123 {plus_minus} 26 key deduced from previous pion-scattering data and with values deduced from other probes. The ratio of {pi}{sup +} + p to {pi}{sup {minus}} + p cross sections was determined experimentally to be 2.60 {plus_minus} 0.11, in agreement with a theoretical value of 2.85. The agreement of these results indicates that the impulse approximation is valid at 50 MeV. Cross sections were also measured for the elastic and collective states in {sup 12}C and were generally described well by distorted wave Born approximation calculations published previously.

  8. The 17 MeV Anomaly in Beryllium Decays and $U(1)$ Portal to Dark Matter

    CERN Document Server

    Chen, Chian-Shu; Lin, Yen-Hsun; Xu, Fanrong

    2016-01-01

    The experiment of Krasznahorkay \\textit{et al} observed the transition of a $\\rm{^{8}Be}$ excited state to its ground state and accompanied by an emission of $e^{+}e^{-}$ pair with 17 MeV invariant mass. This 6.8$\\sigma$ anomaly can be fitted by a new light gauge boson. We consider the new particle as a $U(1)$ gauge boson, $Z'$, which plays as a portal linking dark sector and visible sector. In particular, we study the new $U(1)$ gauge symmetry as a hidden or non-hidden group separately. The generic hidden $U(1)$ model, referred to as dark $Z$ model, is excluded by imposing various experimental constraints. On the other hand, a non-hidden $Z'$ is allowed due to additional interactions between $Z'$ and Standard Model fermions. We also study the implication of the dark matter direct search on such a scenario. We found the search for the DM-nucleon scattering excludes the range of DM mass above 500 MeV. However, the DM-electron scattering for MeV-scale DM is still allowed by current constraints for non-hidden $U...

  9. The 2.5 MeV neutron flux monitor for MAST

    Science.gov (United States)

    Cecconello, M.; Sangaroon, S.; Conroy, S.; Donato, M.; Ericsson, G.; Marini-Bettolo, C.; Ronchi, R.; Stro¨m, P.; Weiszflog, M.; Wodniak, I.; Turnyanskiy, M.; Akers, R.; Cullen, A.; Fitzgerald, I.; McArdle, G.; Pacoto, C.; Thomas-Davies, N.

    2014-07-01

    A proof-of-principle collimated Neutron flux Camera (NC) monitor for the measurement of the 2.45 MeV neutron emission from the deuterium-deuterium fusion reactions has been developed, installed and put into use at the Mega Ampere Spherical Tokamak (MAST). The NC measures the spatial and time resolved volume integrated neutron emissivity in deuterium fusion plasmas in the presence of auxiliary plasma heating along two equatorial and two diagonal lines of sight whose tangency radius can be varied between plasma discharges. This paper describes the NC design principles, their technical realization and its performances illustrated with experimental observations of different plasma scenarios. Neutron count rates in the range 0.1-1.5 MHz are routinely observed allowing time resolutions as high as 1 ms with a statistical uncertainty less than 10% and an energy threshold of 0.5 MeV. Examples of the effect of plasma instabilities on the neutron emission are presented. The good results obtained will be used for the design of the neutron flux camera monitor for MAST Upgrade.

  10. The 2.5 MeV neutron flux monitor for MAST

    Energy Technology Data Exchange (ETDEWEB)

    Cecconello, M., E-mail: marco.cecconello@physics.uu.se [Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala (Sweden); Sangaroon, S.; Conroy, S.; Donato, M.; Ericsson, G.; Marini-Bettolo, C.; Ronchi, R.; Stroem, P.; Weiszflog, M.; Wodniak, I. [Department of Physics and Astronomy, Uppsala University, EURATOM-VR Association, Uppsala (Sweden); Turnyanskiy, M.; Akers, R.; Cullen, A.; Fitzgerald, I.; McArdle, G.; Pacoto, C.; Thomas-Davies, N. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon (United Kingdom)

    2014-07-01

    A proof-of-principle collimated Neutron flux Camera (NC) monitor for the measurement of the 2.45 MeV neutron emission from the deuterium–deuterium fusion reactions has been developed, installed and put into use at the Mega Ampere Spherical Tokamak (MAST). The NC measures the spatial and time resolved volume integrated neutron emissivity in deuterium fusion plasmas in the presence of auxiliary plasma heating along two equatorial and two diagonal lines of sight whose tangency radius can be varied between plasma discharges. This paper describes the NC design principles, their technical realization and its performances illustrated with experimental observations of different plasma scenarios. Neutron count rates in the range 0.1–1.5 MHz are routinely observed allowing time resolutions as high as 1 ms with a statistical uncertainty less than 10% and an energy threshold of 0.5 MeV. Examples of the effect of plasma instabilities on the neutron emission are presented. The good results obtained will be used for the design of the neutron flux camera monitor for MAST Upgrade.

  11. Synthesis and characterisation of starch grafted superabsorbent via 10 MeV electron-beam irradiation.

    Science.gov (United States)

    Zhang, Sufen; Wang, Wei; Wang, Haiyan; Qi, Wenyuan; Yue, Ling; Ye, Qingfu

    2014-01-30

    A starch-graft-polyacrylamide (St-g-PAM) superabsorbent crosslinked by N,N'-methyl bisacrylamide (MBA) was prepared using 10 MeV simultaneous electron beam irradiation at room temperature and subsequent alkaline hydrolysis. The effects of the irradiation dose, acryliamide-to-anhydroglucose unit (AM-to-AGU) ratio and crosslinker amount on the properties of the obtained polymers were evaluated. The structure of the graft copolymer was confirmed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Optimisation treatments were carried out and found for a total dose of 8 kGy, an AM-to-AGU ratio of 4.5 mol mol(-1) and a crosslinker-to-AM ratio of 0.4%mol mol(-1). The obtained superabsorbent polymer showed the maximum absorptions of 1,452 gg(-1) and 83 gg(-1) for distilled water and saline solution, respectively (relative to its own dry weight). The results suggest 10 MeV electron beam irradiation is more efficient than γ-ray irradiation due to its higher energy and dose rate.

  12. Deuterium microscopy using 17 MeV deuteron–deuteron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Reichart, Patrick, E-mail: patrick.reichart@unibw.de; Moser, Marcus; Greubel, Christoph; Peeper, Katrin; Dollinger, Günther, E-mail: guenther.dollinger@unibw.de

    2016-03-15

    Using 17 MeV deuterons as a micrometer focused primary beam, we performed deuterium microscopy by using the deuteron–deuteron (dd) scattering reaction. We describe our new box like detector setup consisting of four double sided silicon strip detectors (DSSSD) with 16 strips on each side, each covering up to 0.5 sr solid angle for coincidence detection. This method becomes a valuable tool for studies of hydrogen incorporation or dynamic processes using deuterium tagging. The background from natural hydrocarbon or water contamination is reduced by the factor 150 ppm of natural abundance of deuterium in hydrogen. Deuterium energies of up to 25 MeV, available at the microprobe SNAKE, are ideal for the analysis of thin freestanding samples so that the scattered particles are transmitted to the detector. The differential cross section for the elastic scattering reaction is about the same as for pp-scattering (~100 mb/sr). The main background due to nuclear reactions is outside the energy window of interest. Deuteron–proton (dp) scattering events give an additional signal for hydrogen atoms, so the H/D-ratio can be monitored in parallel. A deuterium detection limit due to accidental coincidences of 3 at-ppm down to less than 1 at-ppm is demonstrated on deuterated polypropylen sheets as well as thick polycarbonate sheets after various stages of coincidence filtering that is possible with our granular detector.

  13. Dosimetric shield evaluation with tungsten sheet in 4, 6, and 9MeV electron beams.

    Science.gov (United States)

    Fujimoto, Takahiro; Monzen, Hajime; Nakata, Manabu; Okada, Takashi; Yano, Shinsuke; Takakura, Toru; Kuwahara, Junichi; Sasaki, Makoto; Higashimura, Kyoji; Hiraoka, Masahiro

    2014-11-01

    In electron radiotherapy, shielding material is required to attenuate beam and scatter. A newly introduced shielding material, tungsten functional paper (TFP), has been anticipated to become a very useful device that is lead-free, light, flexible, and easily processed, containing very fine tungsten powder at as much as 80% by weight. The purpose of this study was to investigate the dosimetric changes due to TFP shielding for electron beams. TFP (thickness 0-15mm) was placed on water or a water-equivalent phantom. Percentage depth ionization and transmission were measured for 4, 6, and 9MeV electron beams. Off-center ratio was also measured using film dosimetry at depth of dose maximum under similar conditions. Then, beam profiles and transmission with two shielding materials, TFP and lead, were evaluated. Reductions of 95% by using TFP at 0.5cm depth occurred at 4, 9, and 15mm with 4, 6, and 9MeV electron beams, respectively. It is found that the dose tend to increase at the field edge shaped with TFP, which might be influenced by the thickness. TFP has several unique features and is very promising as a useful tool for radiation protection for electron beams, among others.

  14. Radiation damage in InGaAs photodiodes by 1 MeV fast neutrons

    CERN Document Server

    Ohyama, H; Vanhellemont, J; Takami, Y; Sunaga, H

    1998-01-01

    Irradiation damage in In sub 0 sub . sub 5 sub 3 Ga sub 0 sub . sub 4 sub 7 As p-i-n photodiodes by 1 MeV fast neutrons has been studied as a function of fluence for the first time, and the results are discussed in this paper. The degradation of the electrical and optical performance of diodes increases with increasing fluence. The induced lattice defects in the In sub 0 sub . sub 5 sub 3 Ga sub 0 sub . sub 4 sub 7 As epitaxial layers and the InP substrate are studied by Deep Level Transient Spectroscopy (DLTS) methods. In the In sub 0 sub . sub 5 sub 3 Ga sub 0 sub . sub 4 sub 7 As epitaxial layers, hole and electron capture levels are induced by irradiation. The influence of the type of radiation source on the device degradation is then discussed by comparison to 1 MeV electrons with respect to the numbers of knock-on atoms and the nonionizing energy loss (NIEL). The radiation source dependence of performance degradation is attributed to the difference of mass between the two irradiating particles and the p...

  15. Elastic scattering of polarized protons on deuterium at 800 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Weston, G.S.

    1984-07-01

    A specific set of spin transfer coefficients has been measured for proton-deuteron elastic scattering at 800 MeV using an unpolarized liquid deuterium target. The experiment was done using the High Resolution Spectrometer (HRS) at the Los Alamos Meson Physics Facility (LAMPF) with a polarized proton beam. The scattered proton spin direction was determined using the Focal Plane Polarimeter (FPP) of the HRS, which employs a carbon analyzer. Some of the spin dependent parameters measured in this experiment are of considerable interest because they provide selective information about the nucleon-nucleon (NN) amplitude. Since the deuteron is the simplest bound nucleus, pd elastic scattering is particularly well suited for testing multiple scattering theories. These measurements will also be used to eventually determine the full pd collision matrix, which contains all possible information about the scattering process. In addition, the experimental setup is described for a polarized proton-polarized deuterium target spin transfer experiment also done at the HRS at 800 MeV incident proton energy. 71 references.

  16. NEUTRON CAPTURE GAMMA RAY FIELD WITH ENERGY TO 10 MeV FOR METROLOGICAL SUPPORT OF RADIATION PROTECTION DEVICES

    Directory of Open Access Journals (Sweden)

    D. I. Komar

    2016-01-01

    Full Text Available Medical, and technological linear particle accelerators, and nuclear reactors are vastly widespread worldwide today. These facility generate fields of secondary gamma radiation with energy to 10 MeV. Therefore, we have a need to calibrate spectrometric and dosimetric ionization measurement instruments for the energies to 10 MeV. The aim of this work is to determine possibility to use thermal neutron collimator of АТ140 Neutron Calibration Facility with 238Pu-Be fast neutron source (IBN-8-6 for this. Below 3 MeV we use a set of point gamma standard spectrometry sources OSGI. We can acquire gamma rays with energies above 3 MeV using radioactive thermal neutron capture on target, i.e. (n, γ-nuclear reaction. We can use neutron capture gamma-ray from titanium target (to 7 MeV or nickel target (to 10 MeV situated in thermal neutron field for calibration. We can use thermal neutron collimator of АТ140 Neutron Calibration Facility with 238Pu-Be fast neutron source (IBN-8-6 for slowing down neutrons from radionuclide fast neutron sources to thermal energies in polyethylene. Thermal neutron collimator forms a beam from radionuclide source with a significant amount of neutrons with thermal energies. We placed Ti and Ni targets in collimator’s canal. We got experimental spectral data on detection unit BDKG-19M NaI(Tl 63 × 160 mm with nonlinear channel-energy conversion characteristic in range to 10 MeV. For additional filtration we proposed to use polyethylene neutron reflector and lead discs. We experimentally determined that placement of lead discs in collimator in front of the target allows to filter all spectrum while insignificantly weakening target’s emission. Using theoretical and experimental data we proved the ability to calibrate gamma-ray spectrometers in the range to 10 MeV. 

  17. Probing the Cosmic X-Ray and MeV Gamma-Ray Background Radiation through the Anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Yoshiyuki [Stanford Univ., CA (United States). Kavli Inst. for Particle Astrophysics and Cosmology; SLAC National Accelerator Lab., Menlo Park, CA (United States); Murase, Kohta [Inst. for Advanced Study, Princeton, NJ (United States). School of Natural Sciences; Madejski, Grzegorz M. [Stanford Univ., CA (United States). Kavli Inst. for Particle Astrophysics and Cosmology; SLAC National Accelerator Lab., Menlo Park, CA (United States); Uchiyama, Yasunobu [Stanford Univ., CA (United States). Kavli Inst. for Particle Astrophysics and Cosmology; SLAC National Accelerator Lab., Menlo Park, CA (United States); Rikkyo Univ., Tokyo (Japan). Dept. of Physics

    2013-09-24

    While the cosmic soft X-ray background is very likely to originate from individual Seyfert galaxies, the origin of the cosmic hard X-ray and MeV gamma-ray background is not fully understood. It is expected that Seyferts including Compton thick population may explain the cosmic hard X-ray background. At MeV energy range, Seyferts having non-thermal electrons in coronae above accretion disks or MeV blazars may explain the background radiation. We propose that future measurements of the angular power spectra of anisotropy of the cosmic X-ray and MeV gamma-ray backgrounds will be key to deciphering these backgrounds and the evolution of active galactic nuclei (AGNs). As AGNs trace the cosmic large-scale structure, spatial clustering of AGNs exists. We show that e-ROSITA will clearly detect the correlation signal of unresolved Seyferts at 0.5-2 keV and 2-10 keV bands and will be able to measure the bias parameter of AGNs at both bands. Once the future hard X-ray all sky satellites achieve the sensitivity better than 10-12 erg/cm2/s-1 at 10-30 keV or 30-50 keV - although this is beyond the sensitivities of current hard X-ray all sky monitors - angular power spectra will allow us to independently investigate the fraction of Compton-thick AGNs in all Seyferts. We also find that the expected angular power spectra of Seyferts and blazars in the MeV range are different by about an order of magnitude, where the Poisson term, so-called shot noise, is dominant. Current and future MeV instruments will clearly disentangle the origin of the MeV gamma-ray background through the angular power spectrum.

  18. Probing the cosmic x-ray and MeV gamma ray background radiation through the anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Yoshiyuki [Stanford Univ., CA (United States); Murase, Kohta [Inst. for Advanced Study, Princeton, NJ (United States); Madejski, Grzegorz M. [Stanford Univ., CA (United States); Uchiyama, Yasunobu [Stanford Univ., CA (United States); Rikkyo Univ., Tokyo (Japan)

    2013-09-24

    While the cosmic soft X-ray background is very likely to originate from individual Seyfert galaxies, the origin of the cosmic hard X-ray and MeV gamma-ray background is not fully understood. It is expected that Seyferts including Compton thick population may explain the cosmic hard X-ray background. At MeV energy range, Seyferts having non-thermal electrons in coronae above accretion disks or MeV blazars may explain the background radiation. We propose that future measurements of the angular power spectra of anisotropy of the cosmic X-ray and MeV gamma-ray backgrounds will be key to deciphering these backgrounds and the evolution of active galactic nuclei (AGNs). As AGNs trace the cosmic large-scale structure, spatial clustering of AGNs exists. We show that e-ROSITA will clearly detect the correlation signal of unresolved Seyferts at 0.5-2 keV and 2-10 keV bands and will be able to measure the bias parameter of AGNs at both bands. Once future hard X-ray all sky satellites achieve a sensitivity better than 10–12 erg cm–2 s–1 at 10-30 keV or 30-50 keV—although this is beyond the sensitivities of current hard X-ray all sky monitors—angular power spectra will allow us to independently investigate the fraction of Compton-thick AGNs in all Seyferts. We also find that the expected angular power spectra of Seyferts and blazars in the MeV range are different by about an order of magnitude, where the Poisson term, so-called shot noise, is dominant. Current and future MeV instruments will clearly disentangle the origin of the MeV gamma-ray background through the angular power spectrum.

  19. Computer Virus

    Institute of Scientific and Technical Information of China (English)

    高振桥

    2002-01-01

    If you work with a computer,it is certain that you can not avoid dealing, with at least one computer virus.But how much do you know about it? Well,actually,a computer virus is not a biological' one as causes illnesses to people.It is a kind of computer program

  20. Grid Computing

    Indian Academy of Sciences (India)

    2016-05-01

    A computing grid interconnects resources such as high performancecomputers, scientific databases, and computercontrolledscientific instruments of cooperating organizationseach of which is autonomous. It precedes and is quitedifferent from cloud computing, which provides computingresources by vendors to customers on demand. In this article,we describe the grid computing model and enumerate themajor differences between grid and cloud computing.

  1. Response of AGATA segmented HPGe detectors to gamma rays up to 15.1 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Crespi, F.C.L., E-mail: fabio.crespi@mi.infn.it [Dipartimento di Fisica, Università di Milano, Milano I-20133 (Italy); INFN, Sezione di Milano, Milano I-20133 (Italy); Avigo, R.; Camera, F. [Dipartimento di Fisica, Università di Milano, Milano I-20133 (Italy); INFN, Sezione di Milano, Milano I-20133 (Italy); Akkoyun, S. [Department of Physics, Faculty of Science, Cumhuriyet University, Campus 58140, Sivas (Turkey); Ataç, A. [Department of Physics, Faculty of Science, Ankara University, Tandoðan 06100, Ankara (Turkey); Bazzacco, D; Bellato, M. [INFN, Sezione di Padova, Padova I-35131 (Italy); Benzoni, G.; Blasi, N. [INFN, Sezione di Milano, Milano I-20133 (Italy); Bortolato, D. [INFN, Laboratori Nazionali di Legnaro, Legnaro IT-35020 (Italy); Bottoni, S.; Bracco, A. [Dipartimento di Fisica, Università di Milano, Milano I-20133 (Italy); INFN, Sezione di Milano, Milano I-20133 (Italy); Brambilla, S. [INFN, Sezione di Milano, Milano I-20133 (Italy); Bruyneel, B. [CEA-Saclay DSM/IRFU/SPhN, Gif-sur-Yvette 91191 (France); Ceruti, S. [Dipartimento di Fisica, Università di Milano, Milano I-20133 (Italy); INFN, Sezione di Milano, Milano I-20133 (Italy); Ciemała, M. [The Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, 31-342 Krakow (Poland); Coelli, S. [INFN, Sezione di Milano, Milano I-20133 (Italy); Eberth, J. [Institut für Kernphysik, Universität zu Köln, Zülpicher Str. 77, Köln D-50937 (Germany); Fanin, C.; Farnea, E. [INFN, Sezione di Padova, Padova I-35131 (Italy); and others

    2013-03-21

    The response of AGATA segmented HPGe detectors to gamma rays in the energy range 2–15 MeV was measured. The 15.1 MeV gamma rays were produced using the reaction d({sup 11}B,nγ){sup 12}C at E{sub beam}=19.1 MeV, while gamma rays between 2 and 9 MeV were produced using an Am–Be–Fe radioactive source. The energy resolution and linearity were studied and the energy-to-pulse-height conversion resulted to be linear within 0.05%.Experimental interaction multiplicity distributions are discussed and compared with the results of Geant4 simulations. It is shown that the application of gamma-ray tracking allows a suppression of background radiation caused by n-capture in Ge nuclei. Finally the Doppler correction for the 15.1 MeV gamma line, performed using the position information extracted with Pulse-shape analysis is discussed.

  2. Analog computing

    CERN Document Server

    Ulmann, Bernd

    2013-01-01

    This book is a comprehensive introduction to analog computing. As most textbooks about this powerful computing paradigm date back to the 1960s and 1970s, it fills a void and forges a bridge from the early days of analog computing to future applications. The idea of analog computing is not new. In fact, this computing paradigm is nearly forgotten, although it offers a path to both high-speed and low-power computing, which are in even more demand now than they were back in the heyday of electronic analog computers.

  3. Computational composites

    DEFF Research Database (Denmark)

    Vallgårda, Anna K. A.; Redström, Johan

    2007-01-01

    Computational composite is introduced as a new type of composite material. Arguing that this is not just a metaphorical maneuver, we provide an analysis of computational technology as material in design, which shows how computers share important characteristics with other materials used in design...... and architecture. We argue that the notion of computational composites provides a precise understanding of the computer as material, and of how computations need to be combined with other materials to come to expression as material. Besides working as an analysis of computers from a designer’s point of view......, the notion of computational composites may also provide a link for computer science and human-computer interaction to an increasingly rapid development and use of new materials in design and architecture....

  4. Computational chemistry

    OpenAIRE

    2000-01-01

    Computational chemistry has come of age. With significant strides in computer hardware and software over the last few decades, computational chemistry has achieved full partnership with theory and experiment as a tool for understanding and predicting the behavior of a broad range of chemical, physical, and biological phenomena. The Nobel Prize award to John Pople and Walter Kohn in 1998 highlighted the importance of these advances in computational chemistry. With massively parallel computers ...

  5. Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes; Diffusion elastique et inelastique des protons de 2 a 10 MeV par les isotopes du lithium

    Energy Technology Data Exchange (ETDEWEB)

    Laurat, M. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)

  6. Modification of radiobiological effects of 171 MeV protons by elements of physical protection

    Science.gov (United States)

    Bulinina, Taisia; Shurshakov, Vyacheslav; Ivanov, Alexander; Molokanov, Alexander

    2016-07-01

    Space radiation includes protons of various energies. Physical protection is effective in the case of low energy protons (50-100 MeV) and becomes insufficient for radiation with a high part of high-energy protons. In the experiment performed on outbred mice, the purpose of the study was to evaluate the radiobiological effect of 171 MeV protons and protons modified by elements of physical protection of the spacecraft, on a complex of indicators of the functional condition of the system hematopoiesis and the central nervous system in 24 hours after irradiation at 20 cGy dose. The spacecraft radiation protection elements used in the experiment were a construction of wet hygiene wipes called a «protective curtain», and a glass plate imitating an ISS window. Mass thickness of the " protective curtain" in terms of water equivalent was ̴ 6,2 g/cm2. Physical shielding along the path of 171 MeV protons increases their linear energy transfer leading to the absorbed dose elevation and strengthening of the radiobiological effect. In the experiment, the two types of shielding together raised the absorbed dose from 20 to 23.2 cGy. Chemically different materials (glass and water in the wipes) were found to exert unequal modifying effects on physical and biological parameters of the proton-irradiated mice. There was a distinct dose-dependent reduction of bone marrow cellularity within the dose range from 20 cGy to 23.2 cGy in 24 hours after exposure. No modifying effect of the radiation protection elements on spontaneous motor activity was discovered when compared with entrance protons. The group of animals protected by the glass plate exhibited normal orientative-trying reactions and weakened grip with the forelimbs. The effects observed in the experiment indicate the necessity to carry out comprehensive radiobiological researches (physical, biological and mathematical) in assessing the effects of physical protection, that are actual for ensuring radiation safety of crews in

  7. Deuteron-induced reactions on Ni isotopes up to 60 MeV

    Science.gov (United States)

    Avrigeanu, M.; Šimečková, E.; Fischer, U.; Mrázek, J.; Novak, J.; Štefánik, M.; Costache, C.; Avrigeanu, V.

    2016-07-01

    Background: The high complexity of the deuteron-nucleus interaction from the deuteron weak binding energy of 2.224 MeV is also related to a variety of reactions induced by the deuteron-breakup (BU) nucleons. Thus, specific noncompound processes as BU and direct reactions (DR) make the deuteron-induced reactions so different from reactions with other incident particles. The scarce consideration of only pre-equilibrium emission (PE) and compound-nucleus (CN) mechanisms led to significant discrepancies with experimental results so that recommended reaction cross sections of high-priority elements as, e.g., Ni have mainly been obtained by fit of the data. Purpose: The unitary and consistent BU and DR account in deuteron-induced reactions on natural nickel may take advantage of an extended database for this element, including new accurate measurements of particular reaction cross sections. Method: The activation cross sections of 64,61,60Cu, Ni,5765, and 55,56,57,58,59m,60Co nuclei for deuterons incident on natural Ni at energies up to 20 MeV, were measured by the stacked-foil technique and high-resolution gamma spectrometry using U-120M cyclotron of CANAM, NPI CAS. Then, within an extended analysis of deuteron interactions with Ni isotopes up to 60 MeV, all processes from elastic scattering until the evaporation from fully equilibrated compound system have been taken into account while an increased attention is paid especially to the BU and DR mechanisms. Results: The deuteron activation cross-section analysis, completed by consideration of the PE and CN contributions corrected for decrease of the total-reaction cross section from the leakage of the initial deuteron flux towards BU and DR processes, is proved satisfactory for the first time to all available data. Conclusions: The overall agreement of the measured data and model calculations validates the description of nuclear mechanisms taken into account for deuteron-induced reactions on Ni, particularly the BU and

  8. 100 MeV silver ions induced defects and modifications in silica glass

    Energy Technology Data Exchange (ETDEWEB)

    Jadhav, Vijay S.; Deore, Avinash V.; Dahiwale, S.S. [Department of Physics, University of Pune, Pune 411007 (India); Kanjilal, D. [Inter University Accelerator Centre, New Delhi 110067 (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune 411007 (India); Dhole, S.D., E-mail: sanjay@physics.unipune.ac.in [Department of Physics, University of Pune, Pune 411007 (India)

    2014-07-15

    Highlights: •Study of silver ion induced defects and modifications in silica glass. •Variation in oxygen deficiency centres (ODA-II) and nonbridging oxygen hole centres (NBOHC). •Study of structural damage in terms of Urbach energy. -- Abstract: A few silica glass samples having 1 cm{sup 2} area and 0.1 cm thickness were irradiated with 100 MeV energy Ag{sup 7+} ions for the fluences ranging from 1 × 10{sup 12} ions/cm{sup 2} to 5 × 10{sup 13} ions/cm{sup 2}. The optical properties and the corresponding induced defects were characterised by the techniques such as UV–Visible, Photoluminescence (PL), Fourier transform infrared (FTIR), and Electron spin resonance (ESR) spectroscopy. The UV–Visible absorption spectra show two peaks, one at 5 eV and another weak peak at 5.8 eV. A peak observed at 5.0 eV corresponds to B{sub 2} band (oxygen deficiency in SiO{sub 2} network) and the peak at 5.8 eV is due to the paramagnetic defects like E′ centre. The intensities of these peaks found to be increased with increase in ion fluence. It attributes to the increase in the concentration of E′ centres and B{sub 2} band respectively. In addition, the optical band gap energy, Urbach energy and the defects concentration have been calculated using Urbach plot. The optical band gap found to be decreased from 4.65 eV to 4.39 eV and the Urbach energy found to be increased from 60 meV to 162 meV. The defect concentration of nonbridging oxygen hole centres (NBOHC) and E′ centres are found to be increased to 1.69 × 10{sup 13} cm{sup −3} and 3.134 × 10{sup 14} cm{sup −3} respectively. In PL spectra, the peak appeared at 1.92 eV and 2.7 eV envisage the defects of nonbridging oxygen hole centres and B{sub 2α} oxygen deficient centres respectively. ESR spectra also confirms the existence of E′ and NBOHC centres. FTIR spectra shows scissioning of Si-O-Si bonds and the formation of Si-H and Si-OH bonds, which supports to the co-existence of the defects induced by Ag

  9. Two-color infrared FEL facility employing a 250-MeV linac injector of Saga synchrotron light source

    CERN Document Server

    Tomimasu, T; Koga, N; Hashiguchi, Y; Ochiai, Y; Ishibashi, M

    2001-01-01

    A two-color infrared free electron laser (FEL) facility is proposed. This FEL facility will employ a new 250-MeV linac injector of the Saga synchrotron light source (SLS). The linac has two operation modes: short macropulse mode of 1 mu s at 250 MeV is for injection to a 1.4-GeV storage ring and long macropulse mode of 13 mu s at 40 MeV is for the two-color FEL facility. The two-color FEL uses a single electron beam and simultaneously provides both infrared (IR) and far-IR laser pulses for pump-probe studies of quantum-well structures and studying vibrational relaxation of molecules. The Saga SLS will be operated in 2004 to promote material science, bio-medical and industrial applications in Kyushu.

  10. Van Allen Probes observations of prompt MeV radiation belt electron acceleration in nonlinear interactions with VLF chorus

    Science.gov (United States)

    Foster, J. C.; Erickson, P. J.; Omura, Y.; Baker, D. N.; Kletzing, C. A.; Claudepierre, S. G.

    2017-01-01

    Prompt recovery of MeV (millions of electron Volts) electron populations in the poststorm core of the outer terrestrial radiation belt involves local acceleration of a seed population of energetic electrons in interactions with VLF chorus waves. Electron interactions during the generation of VLF rising tones are strongly nonlinear, such that a fraction of the relativistic electrons at resonant energies are trapped by waves, leading to significant nonadiabatic energy exchange. Through detailed examination of VLF chorus and electron fluxes observed by Van Allen Probes, we investigate the efficiency of nonlinear processes for acceleration of electrons to MeV energies. We find through subpacket analysis of chorus waveforms that electrons with initial energy of hundreds of keV to 3 MeV can be accelerated by 50 keV-200 keV in resonant interactions with a single VLF rising tone on a time scale of 10-100 ms.

  11. Measurement of np elastic scattering spin-spin correlation parameters at 484, 634, and 788 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Garnett, R.W.

    1989-03-01

    The spin-spin correlation parameters C/sub LL/ and C/sub SL/ were measured for np elastic scattering at the incident neutron kinetic energy of 634 MeV. Good agreement was obtained with previously measured data. Additionally, the first measurement of the correlation parameter C/sub SS/ was made at the three energies, 484, 634, and 788 MeV. It was found that the new values, in general, do not agree well with phase shift predictions. A study was carried out to determine which of the isospin-0 partial waves will be affected by this new data. It was found that the /sup 1/P/sub 1/ partial wave will be affected significantly at all three measurement energies. At 634 and 788 MeV, the /sup 3/S/sub 1/ phase shifts will also change. 29 refs., 21 figs., 16 tabs.

  12. Measurement of the Cross Section and Analyzing Powers for d+p Elastic Scattering at 180 MeV

    Science.gov (United States)

    Bailey, C. D.; Stephenson, E. J.; Bacher, A. D.; Micherdzinska, A. M.; Messchendorp, J. G.; Biegun, A.; Eslami-Kalantari, M.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Mardanpour, H.; Moeini, H.; Ramazani-Moghaddam-Arani, A.; Shende, S. V.; Wörtche, H.; Stephan, E.; Kistryn, St.; Sekiguchi, K.

    2008-04-01

    We have measured cross sections and analyzing powers for various d+d reaction channels, including d+d elastic and d+d->p+t at 130 MeV and 180 MeV, with the hope of providing a testing ground for new 4-body theoretical predictions. These data were collected at the KVI cyclotron (Groningen) using the Big Bite spectrometer and a polarized deuteron beam. In addition to the d+d channels, we also measured the cross section and analyzing powers (Ay and Ayy) for d+p elastic scattering at the same energies for comparison with existing data and with 3-body calculations (with and without three nucleon forces). We report here our results for the d+p elastic data at 180 MeV. The analysis procedure will be reviewed and several preliminary results will be shown.

  13. Molecular dynamic simulation of secondaryion ion emission from an Al sample bombarded with MeV heavy ions

    Institute of Scientific and Technical Information of China (English)

    薛建明; 今西信嗣

    2002-01-01

    Sputtering yields and kinetic energy distributions (KED) of Al atomic ions ejected from a pure aluminium sampleunder MeV silicon ion bombardment were simulated with the molecular dynamic method. Since the electronic energyloss Se is much higher than the nuclear energy loss Sn when the incident ion energy is as high as several MeV, the Seeffect was also taken into consideration in the simulation. It was found that the simulated sputtering yield fits well withthe experimental data and the electronic energy loss has a slight effect at incident ion energies higher than 4 MeV. Thesimulated secondary ion KED spectrum is a little lower in the peak energy and narrower in the peak width than thatin the experiment.

  14. Channeling and coherent bremsstrahlung effects for relativistic positrons and electrons. [16 to 28 MeV, orientation

    Energy Technology Data Exchange (ETDEWEB)

    Walker, R. L.

    1976-03-22

    Channeling of positrons in single crystals of silicon was observed in transmission and scattering measurements for incident energies from 16 to 28 MeV. In addition, the spectral dependence upon crystal orientation of the forward coherent bremsstrahlung produced by beams of 28-MeV positrons and electrons incident upon a 5 ..mu..m thick single crystal of silicon was measured with a NaI photon spectrometer. Effects of channeling and perhaps of the nonvalidity of the first Born approximation were observed for beam directions near the (111) axis of the crystal, and coherent peaks near 0.5 MeV were observed for a compound interference direction, in agreement with first-order theoretical calculations. 32 fig.

  15. Research Programme for the 660 Mev Proton Accelerator Driven MOX-Plutonium Subcritical Assembly

    CERN Document Server

    Barashenkov, V S; Buttseva, G L; Dudarev, S Yu; Polanski, A; Puzynin, I V; Sissakian, A N

    2000-01-01

    The paper presents a research programme of the Experimental Acclerator Driven System (ADS), which employs a subcritical assembly and a 660 MeV proton acceletator operating at the Laboratory of Nuclear Problems of the JINR, Dubna. MOX fuel (25% PuO_2 + 75% UO_2) designed for the BN-600 reactor use will be adopted for the core of the assembly. The present conceptual design of the experimental subcritical assembly is based on a core of a nominal unit capacity of 15 kW (thermal). This corresponds to the multiplication coefficient k_eff = 0.945, energetic gain G = 30 and the accelerator beam power 0.5 kW.

  16. A detailed test of a BSO calorimeter with 100-800 MeV positrons

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, T., E-mail: ishikawa@lns.tohoku.ac.jp [Research Center for Electron Photon Science, Tohoku University, Sendai 982-0826 (Japan); Fujimura, H.; Hashimoto, R.; Kaida, S.; Kasagi, J.; Kitazawa, R.; Kuwasaki, S.; Nakamura, A.; Nawa, K.; Okada, Y.; Sato, M.; Shimizu, H.; Suzuki, K. [Research Center for Electron Photon Science, Tohoku University, Sendai 982-0826 (Japan); Tajima, Y. [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Takahashi, S.; Tsuchikawa, Y.; Yamazaki, H. [Research Center for Electron Photon Science, Tohoku University, Sendai 982-0826 (Japan); Yoshida, H.Y. [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan)

    2012-12-01

    A performance test has been made for an electro-magnetic calorimeter prototype comprised four identical BSO crystals arranged in a 2 Multiplication-Sign 2 matrix by utilizing a positron beam in the energy range from 100 to 800 MeV. The size of each crystal is 40 Multiplication-Sign 40 Multiplication-Sign 210 mm{sup 3}. This is the world's largest BSO single crystal ever used as a photon detector. The obtained energy resolution is ({sigma}{sub E}/E){sup 2}=((1.71%{+-}0.03%)/{radical}(E)){sup 2}+(1.12%{+-}0.08%){sup 2} at room temperature, where E is the incident positron energy given in GeV. A BGO calorimeter having the same geometry has been employed in the performance test for comparison. The basic scintillation characteristics of BSO crystals measured without the beam are also presented.

  17. An 800-MeV proton radiography facility for dynamic experiments

    CERN Document Server

    King, N S P; Adams, K; Alrick, K R; Amann, J F; Balzar, S; Barnes, P D J; Crow, M L; Cushing, S B; Eddleman, J C; Fife, T T; Flores, P; Fujino, D; Gallegos, R A; Gray, N T; Hartouni, E P; Hogan, G E; Holmes, V H; Jaramillo, S A; Knudsson, J N; London, R K; Lopez, R R; McDonald, T E; McClelland, J B; Merrill, F E; Morley, K B; Morris, C L; Naivar, F J; Parker, E L; Park, H S; Pazuchanics, P D; Pillai, C; Riedel, C M; Sarracino, J S; Shelley, F E J; Stacy, H L; Takala, B E; Thompson, R; Tucker, H E; Yates, G J; Ziock, H J; Zumbro, J D

    1999-01-01

    The capability has successfully been developed at the Los Alamos Nuclear Science Center (LANSCE) to utilize a spatially and temporally prepared 800 MeV proton beam to produce proton radiographs. A series of proton bursts are transmitted through a dynamic object and transported, via a unique magnetic lens system, to an image plane. The magnetic lens system permits correcting for the effects of multiple coulomb scattering which would otherwise completely blur the spatially transmitted information at the image plane. The proton radiographs are recorded either on a time integrating film plate or with a recently developed multi-frame electronic imaging camera system. The latter technique permits obtaining a time dependent series of proton radiographs with time intervals (modulo 358 ns) up to many microseconds and variable time intervals between images. One electronically shuttered, intensified, CCD camera is required per image. These cameras can detect single protons interacting with a scintillating fiber optic ar...

  18. Preequilibrium particle emission in 250 MeV {sup 16}O + {sup 116}Sn reaction

    Energy Technology Data Exchange (ETDEWEB)

    Barlini, S.; Kravchuk, V.L.; Gramegna, F. [INFN, Laboratori Nazionali di Legnaro Padova (Italy)] (and others)

    2005-07-01

    A certain progress in understanding the phenomenon of the Preequilibrium (fast) light charged particle and neutron Emission (PE) was achieved in the last two decades. However, there is a strong need to study systematically the dependence of the PE emission on the reaction mass asymmetry and the projectile energy. In the present work we present the results on the PE proton and alpha-particle multiplicities and the total energy loss of the composite system formed in fusion reaction E{sub b}eam=250 MeV (15.6 MeV/u) {sup 16}O + {sup 116}Sn. The experiment was performed at the Legnaro National Laboratory using a 1 ns (FWHM) pulsed beam provided by the TANDEM-ALPI acceleration system.

  19. Surface Morphology and Phase Stability of Titanium Foils Irradiated by 136 MeV 136Xe

    CERN Document Server

    Sadi, S; Loveland, W; Watson, P R; Greene, J P; Zhu, S; Zinkann, G

    2013-01-01

    A stack of titanium foils was irradiated with 136 MeV 136Xe to study microstructure damage and phase stability of titanium upon irradiation. X- ray diffraction, scanning electron microscopy/energy dispersive spectroscopy and atomic force microscopy were used to study the resulting microstructure damage and phase stability of titanium. We observed the phase transfor- mation of polycrystalline titanium from alpha-Ti (hexagonally closed packed (hcp)) to face centered cubic (fcc) after irradiation with 2.2 x 1015 ions/cm2. Irradiation of Ti with 1.8 x 1014-2.2 x 1015 ions/cm2 resulted in the forma- tion of voids, hillocks, dislocation loops, dislocation lines, as well as polygonal ridge networks.

  20. Impurity induced neutralization of MeV energy protons in JET plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Gondhalekar, A. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Korotkov, A.A. [AF Ioffe Institute, Saint Petersburg (Russian Federation)

    1994-07-01

    A model elucidating the role of carbon and beryllium, the main impurities in JET plasmas, in neutralizing MeV energy protons, which arise during ICRF heating of deuterium plasmas in the hydrogen minority heating mode D(H), and from D-D fusion reactions, is presented. The model establishes charge transfer from hydrogen-like impurity ions to protons as the main process for neutralization. Calculations for deducing the proton energy distribution function from measured hydrogen flux are described. The validity of the model is tested by using it to described the measured flux in different conditions of plasma heating and fueling. Further, it is used to deduce the background thermal deuterium atom density at the plasma center. 9 refs., 6 figs.

  1. MeV X-ray imaging using plastic scintillating fiber area detectors: a simulation study.

    Science.gov (United States)

    Tang, Shi-Biao; Ma, Qingli; Yin, Zejie; Zhu, Daming

    2008-02-01

    Due to their low cost, flexibility, and convenience for long distance data transfer, plastic scintillating fibers (PSFs) have been increasingly used in building detectors or sensors for detecting various radiations and imaging. In this work, the possibility of using PSF coupled with charge-coupled devices (CCD) to build area detectors for X-ray imaging is studied using a Monte Carlo simulation. The focus is on X-ray imaging with energy from a few 100 keV to about 20 MeV. It is found that the efficiency of PSF in detecting X-ray in this energy range is low. The performance can be improved by coating a PSF with X-ray absorption layers and the MTF of the system is presented. It seems possible to build such area detectors with PSFs for imaging hard X-rays under certain environment.

  2. MeV Neutron Production from Thermal Neutron Capture in {6}^Li Simulated with Geant4

    CERN Document Server

    Santoro, Valentina; Bentley, Phillip M

    2015-01-01

    Various Li compounds are commonly used at neutron facilities as neutron absorbers. These compounds provide one of the highest ratios of neutron attenuation to $\\gamma$-ray production. Unfortunately, the usage of these compounds can also give rise to fast neutron emission with energies up to almost 16 MeV. Historically, some details in this fast neutron production mechanism can be absent from some modeling packages under some optimization scenarios. In this work, we tested Geant4 to assess the performance of this simulation toolkit for the fast neutron generation mechanism. We compare the results of simulations performed with Geant4 to available measurements. The outcome of our study shows that results of the Geant4 simulations are in good agreement with the available measurements for $^6$Li fast neutron production, and suitable for neutron instrument background evaluation at spallation neutron sources.

  3. Activation cross sections of proton induced nuclear reactions on gold up to 65 MeV

    CERN Document Server

    Ditrói, F; Takács, S; Hermanne, A

    2016-01-01

    Activation cross sections of proton induced reactions on gold for production of $^{197m,197g,195m,195g, 193m,193g,192}$Hg, $^{196m,196g(cum),195g(cum),194,191(cum)}$Au, $^{191(cum)}$Pt and $^{192}$Ir were measured up to 65 MeV proton energy, some of them for the first time. The new data are in acceptably good agreement with the recently published earlier experimental data in the overlapping energy region. The experimental data are compared with the predictions of the TALYS 1.6 (results in TENDL-2015 on-line library) and EMPIRE 3.2 code.

  4. Low-energy theorems for nucleon-nucleon scattering at Mπ=450 MeV

    Science.gov (United States)

    Baru, V.; Epelbaum, E.; Filin, A. A.

    2016-07-01

    We apply the low-energy theorems to analyze the recent lattice QCD results for the two-nucleon system at a pion mass of Mπ≃450 MeV obtained by the NPLQCD Collaboration. We find that the binding energies of the deuteron and dineutron are inconsistent with the low-energy behavior of the corresponding phase shifts within the quoted uncertainties and vice versa. Using the binding energies of the deuteron and dineutron as input, we employ the low-energy theorems to predict the phase shifts and extract the scattering length and the effective range in the S31 and S10 channels. Our results for these quantities are consistent with those obtained by the NPLQCD Collaboration from effective field theory analyses but are in conflict with their determination based on the effective-range approximation.

  5. Activation cross sections of proton induced nuclear reactions on ytterbium up to 70 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Tarkanyi, F. [Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), 4026 Debrecen, Bem ter 18/c (Hungary); Hermanne, A. [Cyclotron Laboratory, Vrije Universiteit Brussel (VUB), 1090 Brussels (Belgium); Takacs, S.; Ditroi, F. [Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), 4026 Debrecen, Bem ter 18/c (Hungary); Kiraly, B. [Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), 4026 Debrecen, Bem ter 18/c (Hungary)], E-mail: kiralyb@atomki.hu; Yamazaki, H.; Baba, M.; Mohammadi, A. [Cyclotron and Radioisotope Center (CYRIC), Tohoku University, Sendai 980-8578 (Japan); Ignatyuk, A.V. [Institute of Physics and Power Engineering (IPPE), Obninsk 249020 (Russian Federation)

    2009-09-01

    Cross sections of proton induced nuclear reactions on ytterbium were measured up to 70 MeV by using the standard stacked foil irradiation technique and high-resolution gamma-ray spectroscopy. Experimental cross sections and derived integral yields are reported for the first time for the {sup nat}Yb(p,xn){sup 173,172mg,171mg,170,167}Lu, {sup nat}Yb(p,x){sup 175cum,166cum}Yb and {sup nat}Yb(p,x){sup 173ind,172ind,168,167cum,165cum}Tm reactions. No earlier experimental cross section data were found in the literature. The experimental data were compared to and analyzed with the results of the theoretical model code ALICE-IPPE. Production routes of medical radioisotope {sup 167}Tm are discussed.

  6. New frontier of laser particle acceleration: driving protons to 80 MeV by radiation pressure

    CERN Document Server

    Kim, I Jong; Kim, Chul Min; Kim, Hyung Taek; Lee, Chang-Lyoul; Choi, Il Woo; Singhal, Himanshu; Sung, Jae Hee; Lee, Seong Ku; Lee, Hwang Woon; Nickles, Peter V; Jeong, Tae Moon; Nam, Chang Hee

    2014-01-01

    The radiation pressure acceleration (RPA) of charged particles has been considered a challenging task in laser particle acceleration. Laser-driven proton/ion acceleration has attracted considerable interests due to its underlying physics and potential for applications such as high-energy density physics, ultrafast radiography, and cancer therapy. Among critical issues to overcome the biggest challenge is to produce energetic protons using an efficient acceleration mechanism. The proton acceleration by radiation pressure is considerably more efficient than the conventional target normal sheath acceleration driven by expanding hot electrons. Here we report the generation of 80-MeV proton beams achieved by applying 30-fs circularly polarized laser pulses with an intensity of 6.1 x 1020 W/cm2 to ultrathin targets. The radiation pressure acceleration was confirmed from the obtained optimal target thickness, quadratic energy scaling, polarization dependence, and 3D-PIC simulations. We expect this fast energy scalin...

  7. Proposal to observe half-bare electrons on a 45-MeV linac

    Science.gov (United States)

    Trofymenko, S. V.; Shul'ga, N. F.; Delerue, N.; Jenzer, S.; Khodnevych, V.; Migayron, A.

    2017-07-01

    The experimental investigation of the transition radiation (TR) generated by a “half-bare” electron having the proper field different from the Coulomb one is proposed. The electrons in half-bare state are intended to be obtained in the result of their crossing of a conducting screen. We propose to investigate the influence of the half-bare state of electron in this process upon TR generated by such electron on a downstream OTR screen situated on some distance along the direction of the electron beam from the upstream screen which “undresses” the particle. Calculations are presented for the case of a 45 MeV linac and the distance between the screens in the region between 100 mm and 300 mm. The proposed experiment is expected to reveal new features of TR signal in such process comparing to previous measurements.

  8. Preliminary shielding assessment for the 100 MeV proton linac (KOMAC).

    Science.gov (United States)

    Lee, Young-Ouk; Cho, Y S; Chang, J

    2005-01-01

    The Proton Engineering Frontier Project is building the Korea Multipurpose Accelerator Complex facilities from 2002 to 2012, which consists of a high-current 100 MeV proton linear accelerator and various beam-lines. This paper provides a preliminary estimate of the shielding required for the 20 mA proton linac and the beam-dump. For an accurate information on secondary neutron production from the guiding magnet and primary heat sink of the beam dump, proton-induced 63Cu and 65Cu cross section data were evaluated and applied to shielding calculations. The required thickness of the concrete was assessed by a simple line-of-sight model for the lateral shielding of the beam-line and the full shielding of the beam dump. Monte Carlo simulations were also performed using the MCNPX code to obtain the source term and attenuation coefficients for the three-dimensional lateral shielding model of the beam-line.

  9. Analytic and experimental decay heat determinations of 800-MeV proton irradiated aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Kmetyk, L.N.; Sommer, W.F.

    1981-10-01

    Postirradiation radiochemistry analysis of 800-MeV proton irradiated ultrahigh purity aluminum has been done with standard gamma-ray counting equipment determining the Na/sup 22/ activity in the activated aluminum. Results are compared to predicted values obtained from CINDER, a general nuclide depletion and fission-product code. This program can be used easily to calculate the activity of materials under arbitrary irradiation, provided that the source terms for the various radionuclides produced are known. The required production cross sections have been calculated by using the nucleon-meson transport code NMTC to determine the nuclear reactions produced by the protons, and the theory of Lindhard et al. to evaluate the resultant damage energy deposited in the target.

  10. Calibration of imaging plates to electrons between 40 and 180 MeV.

    Science.gov (United States)

    Rabhi, N; Bohacek, K; Batani, D; Boutoux, G; Ducret, J-E; Guillaume, E; Jakubowska, K; Thaury, C; Thfoin, I

    2016-05-01

    This paper presents the response calibration of Imaging Plates (IPs) for electrons in the 40-180 MeV range using laser-accelerated electrons at Laboratoire d'Optique Appliquée (LOA), Palaiseau, France. In the calibration process, the energy spectrum and charge of electron beams are measured by an independent system composed of a magnetic spectrometer and a Lanex scintillator screen used as a calibrated reference detector. It is possible to insert IPs of different types or stacks of IPs in this spectrometer in order to detect dispersed electrons simultaneously. The response values are inferred from the signal on the IPs, due to an appropriate charge calibration of the reference detector. The effect of thin layers of tungsten in front and/or behind IPs is studied in detail. GEANT4 simulations are used in order to analyze our measurements.

  11. Enhanced diffraction of MeV γ-rays by mosaic crystals

    Science.gov (United States)

    Matsuba, Shunya; Hayakawa, Takehito; Shizuma, Toshiyuki; Nishimori, Nobuyuki; Nagai, Ryoji; Sawamura, Masaru; Angell, Christopher T.; Fujiwara, Mamoru; Hajima, Ryoichi

    2016-11-01

    The diffraction of γ-rays by mosaic Si crystals with thicknesses of 20, 40, and 80 mm and by a 2-mm-thick perfect Si crystal in a transmission Laue geometry was measured using a high-flux 60Co source with an intensity of 2.2 TBq. The measured diffraction intensities at 1.17 and 1.33 MeV using 40- and 80-mm-thick mosaic crystals were enhanced by a factor of approximately 8.6 compared with those of the perfect Si crystal. The integrated reflectivity is well described in statistical dynamical theory by taking into account γ-ray absorption inside the crystals.

  12. Alpha-induced reactions on selenium between 11 and 15 MeV

    Science.gov (United States)

    Fiebiger, Stefan; Slavkovská, Zuzana; Giesen, Ulrich; Göbel, Kathrin; Heftrich, Tanja; Heiske, Annett; Reifarth, René; Schmidt, Stefan; Sonnabend, Kerstin; Thomas, Benedikt; Weigand, Mario

    2017-07-01

    The production of 77,79,85,85m Kr and 77Br via the reaction Se(α ,x) was investigated between {E}α =11 and 15 MeV using the activation technique. The irradiation of natural selenium targets on aluminum backings was conducted at the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Germany. The spectroscopic analysis of the reaction products was performed using a high-purity germanium detector located at PTB and a low energy photon spectrometer detector at the Goethe University Frankfurt, Germany. Thick-target yields were determined. The corresponding energy-dependent production cross sections of 77,79,85,85m Kr and 77Br were calculated from the thick-target yields. Good agreement between experimental data and theoretical predictions using the TALYS-1.6 code was found.

  13. Study on the microwave ion source of 100-MeV proton linac

    CERN Document Server

    Kwon, Hyeok-Jung

    2016-01-01

    A microwave ion source is used as an ion source of 100-MeV proton accelerator at Korea Multipurpose Accelerator Complex (KOMAC). The specifications of the ion source are 50 keV in energy and 20 mA in peak current. The plasma is operated in CW mode using magnetron and the pulse beam is extracted using semiconductor switch located in the extraction power supply. The beam characteristics were measured based on the pulse voltage and current. A test stand was also installed to study the beam characteristics of the ion source in off-line. In this paper, the pulse beam characteristics of the ion source are presented and the installation of the test stand is reported.

  14. Dislocation Climb Sources Activated by 1 MeV Electron Irradiation of Copper-Nickel Alloys

    DEFF Research Database (Denmark)

    Barlow, P.; Leffers, Torben

    1977-01-01

    Climb sources emitting dislocation loops are observed in Cu-Ni alloys during irradiation with 1 MeV electrons in a high voltage electron microscope. High source densities are found in alloys containing 5, 10 and 20% Ni, but sources are also observed in alloys containing 1 and 2% Ni. The range......, thermodynamically, there is not complete miscibility in the Cu-Ni system as implied by the published phase diagrams. It is furthermore suggested that these precipitates are platelets of Ni atoms on {100} planes, which would account for the formation of the rectangular loops. The binding energy between vacancies...... of irradiation temperatures corresponding to the highest source densities is approximately 350°–500°C. The climb sources are not related to any pre-existing dislocations resolved in the microscope. The sources emit three types of loop: ‘rectangular’ loops with a100 Burgers vector and {100} habit plane, normal...

  15. Efficient production and diagnostics of MeV proton beams from a cryogenic hydrogen ribbon

    Science.gov (United States)

    Velyhan, A.; Giuffrida, L.; Scuderi, V.; Perin, J. P.; Chatain, D.; Garcia, S.; Bonnay, P.; Dostal, J.; Ullschmied, J.; Dudzak, R.; Krousky, E.; Cykhardt, J.; Prokupek, J.; Pfeifer, M.; Rosinski, M.; Krasa, J.; Brabcova, K.; De Napoli, M.; Lastovicka, T.; Margarone, D.

    2017-06-01

    A solid hydrogen thin ribbon, produced by the cryogenic system ELISE (Experiments on Laser Interaction with Solid hydrogEn) target delivery system, was experimentally used at the PALS kJ-laser facility to generate intense proton beams with energies in the MeV range. This sophisticated target system operating at cryogenic temperature (~ 10 K) continuously producing a 62 μm thick target was combined with a 600 J sub-nanosecond laser pulse to generate a collimated proton stream. The accelerated proton beams were fully characterized by a number of diagnostics. High conversion efficiency of laser to energetic protons is of great interest for future potential applications in non-conventional proton therapy and fast ignition for inertial confinement fusion.

  16. Spallation yield of neutrons produced in thick lead target bombarded with 250 MeV protons

    Energy Technology Data Exchange (ETDEWEB)

    Chen, L. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Ma, F., E-mail: mf@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zhanga, X.Y.; Ju, Y.Q.; Zhang, H.B.; Ge, H.L.; Wang, J.G. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zhou, B. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Li, Y.Y.; Xu, X.W. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Luo, P.; Yang, L.; Zhang, Y.B.; Li, J.Y.; Xu, J.K. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Liang, T.J. [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang, S.L. [University of Chinese Academy of Sciences, Beijing 100049 (China); Yang, Y.W.; Gu, L. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2015-01-01

    The neutron yield from thick target of Pb irradiated with 250 MeV protons has been studied experimentally. The neutron production was measured with the water-bath gold method. The thermal neutron distributions in the water were determined according to the measured activities of Au foils. Corresponding results calculated with the Monte Carlo code MCNPX were compared with the experimental data. It was found out that the Au foils with cadmium cover significantly changed the spacial distribution of the thermal neutron field. The corrected neutron yield was deduced to be 2.23±0.19 n/proton by considering the influence of the Cd cover on the thermal neutron flux.

  17. Planar optical waveguides formed in β-BBO by MeV O+ implantation

    Institute of Scientific and Technical Information of China (English)

    WANG Xuelin; WANG Keming; CHEN Feng; LU Qingming; MA Hongji; NIE Rui

    2007-01-01

    The planar waveguides have been fabricated in z-cutβ-B2O4 crystal by 2.8 MeV O+ion implantation with the doses of 8×1014 and 2×1015ions/cm2 at room temperature.The waveguides were characterized by the prismcoupling method.The dark modes are measured before and after the annealing at 300℃ for 20 and 40 min in air.The refractive index profile is reconstructed Using the reflectivity calculation method.It is found that relatively 1arge positive changes of extraordinary refractive indices happen in the guiding regions,and a slight change increases with the doses,which are different from most of the observed ion-implanted waveguides.

  18. Neutrino Interaction Calculations from MeV to GeV Region

    CERN Document Server

    Amaro, J E; Valverde, M; Vicente-Vacas, M J

    2008-01-01

    The Quasi-Elastic (QE) contribution of the nuclear inclusive electron model developed in Nucl. Phys. A627 543 (1997) is extended to the study of neutrino/antineutrino Charged Current (CC) and Neutral Current (NC) induced nuclear reactions at intermediate energies. Long range nuclear (RPA) correlations, Final State Interaction (FSI) and Coulomb corrections are included within the model. RPA correlations are shown to play a crucial role in the whole range (100--500 MeV) of studied neutrino energies. Results for inclusive muon capture for different nuclei through the Periodic Table are also discussed. In addition, and by means of a Monte Carlo cascade method to account for the rescattering of the outgoing nucleon, we also study the CC and NC inclusive one nucleon knockout reactions off nuclei.

  19. Physical and chemical response of 70 MeV carbon ion irradiated Kapton-H polymer

    Indian Academy of Sciences (India)

    H S Virk; P S Chandi; A K Srivastava

    2001-10-01

    Physical and chemical responses of 70 MeV carbon ion irradiated Kapton-H polymer were studied by using UV-visible, FTIR and XRD techniques. The ion fluences ranging from 9.3 × 1011–9 × 1013 ions cm–2 were used. Recorded UV-visible spectra clearly showed a decrease in absorption initially with fluence, but for the higher fluences it showed a recovery characteristic. A decrease in band-gap energy of 0.07 eV was observed. The FTIR analysis indicated the high resistance to radiation induced degradation of polymer. The diffraction pattern of Kapton-H indicates that this polymer is semi-crystalline in its nature. In case of irradiated one, there was an average increase of crystallite size by 20%, but diffuse pattern indicates that there was a decrease in crystallinity, which may be attributed to the formation of complex structure induced by the cross-linking of the polymeric chains.

  20. Fission Fragments Produced from Proton Irradiation of Thorium Between 40 and 200 MeV

    CERN Document Server

    Engle, Jonathan W; Weidner, John W; Fassbender, Michael E; Bach, Hong T; Ullmann, John L; Couture, Aaron J; Bitteker, Leo J; Gulley, Mark S; John, Kevin D; Birnbaum, Eva R; Nortier, Francois M

    2013-01-01

    The cross sections for the formation of five residual radionuclides (72Se, 97Zr, 112Pd, 125Sb, and 147Nb) from 40- to 200-MeV proton irradiation of thorium have been measured and are reported. The atomic masses of these fragments span the expected mass distribution of radionuclides formed by fission of the target nucleus. Especially in mass regions corresponding to transitions between different relaxation mechanisms employed by available models, these data are expected to be useful to the improvement of high-energy transport codes. The predictions of the event generators incorporated into the latest release of the Monte Carlo N-Particle code (MCNP6) are compared with data measured in this work in the hope that these results may be useful to the continued process of code verification and validation in MCNP6.

  1. Development of the 50-Mev DTL for the Jaeri/Kek Joint Project

    CERN Document Server

    Naito, F; Kubota, C; Kato, T; Saitô, Y; Takasaki, E; Yamazaki, Y; Kobayashi, S; Sekikawa, K; Shibusawa, M; Kabeya, Zenzaburo; Tajiri, K; Kawasumi, T

    2000-01-01

    An Alvaretz-type DTL, to accelerate the H- ion beam from 3 to 50 MeV, is being constructed as the injector for the JAERI/KEK Joint Project. The following components of the DTL have been developed: (1) a cylindrical tank, made by copper electroforming; (2) rf contactors; (3) a pulse-excited quadrupole magnet with a hollow coil made by copper electroforming; (4) a switching-regulator-type pulsed-power supply for the quadrupole magnet. High-power tests of the components have been conducted using a short-model tank. Moreover a breakdown experiment of the copper electrodes has been carried out in order to study the properties of several kinds of copper materials.

  2. Physical and thermal properties of 8 MeV electron beam irradiated HPMC polymer films

    Energy Technology Data Exchange (ETDEWEB)

    Sangappa [Department of Studies in Physics, Mangalore University, Mangalagangotri 574 199 (India)], E-mail: sangappa@mangaloreuniversity.ac.in; Demappa, T.; Mahadevaiah [Department of Polymer Science, Sir M V, P G Center, University of Mysore, Mandya 575 007 (India); Ganesha, S. [Microtron Center, Mangalore University, Mangalagangotri 574 199 (India); Divakara, S. [Department of Physics, East Point College of Engineering and Technology, Bangalore 560049 (India); Pattabi, Manjunath [Department of Material Science, Mangalore University, Mangalagangotri 574 199 (India); Somashekar, R. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006 (India)

    2008-09-15

    Microstructural modification in hydroxypropyl methylcellulose (HPMC) polymer films induced by electron irradiation is studied. Irradiation was performed in air at room temperature using a 8 MeV electron accelerator at doses of 25, 50, 75 and 100 kGy. Irradiation can be used to crosslink or degrade the desired component or to fix the polymer morphology. Changes in microstructural parameters, crystallinity and thermal properties in virgin and irradiated HPMC films have been studied using wide angle X-ray scattering data and differential scanning calorimetry. The heat of fusion and the degree of crystallinity are found to be highest for unirradiated HPMC and the crystallite size is larger in virgin HPMC films.

  3. Proton-Deuteron Break-Up Measurements with Bina at 135 MeV

    Science.gov (United States)

    Eslami-Kalantari, M.; Amir-Ahmadi, H. R.; Biegun, A.; Gašparić, I.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Kistryn, St.; Kozela, A.; Mardanpour, H.; Messchendorp, J. G.; Moeini, H.; Ramazani-Moghaddam-Arani, A.; Shende, S. V.; Stephan, E.; Sworst, R.

    High-precision measurements of the proton-deuteron elastic and break-up reaction have been performed in the past at KVI and elsewhere with the aim to study three-nucleon force (3NF) effects. In the present work, we explored 3NF effects in the break-up scattering process by performing a measurement of vector analyzing powers and differential cross sections using a 135 MeV polarized-proton beam impinging on a liquid-deuterium target. For this study, we used a new experimental setup, Big Instrument for Nuclear-polarization Analysis, BINA, which covers almost the entire kinematical phase space of the break-up reaction. The results are interpreted with the help of state-of-the-art Faddeev calculations.

  4. Calculation of A x for the Proton-Deuteron Breakup Reaction at 135 MeV

    Science.gov (United States)

    Eslami-Kalantari, M.; Mehmandoost-Khajeh-Dad, A. A.; Shafaei, M. A.; Amir-Ahmadi, H. R.; Biegun, A.; Gašparic, I.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Kistryn, St.; Kozela, A.; Mardanpour, H.; Messchendorp, J. G.; Moeini, H.; Ramazani-Moghaddam-Arani, A.; Shende, S. V.; Stephan, E.; Sworst, R.

    2013-08-01

    Observables in proton-deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects (3NF). Several facilities in the world, including Kernfysisch Versneller Instituut (KVI), allow a detailed study a few-nucleon interaction below the pion-production threshold exploiting polarized proton and deuteron beams. In this contribution we explored 3NF effects in the break-up scattering process by performing a measurement of differential cross section and the analyzing power, especially the x component of the analyzing power, using a 135 MeV polarized-proton beam impinging on a liquid-deuteron target. The proton-deuteron breakup reaction leads to a final state with three free particles and a rich phase space that allows us to study observables for continuous set of kinematical configurations of the outgoing nucleons. The results are interpreted with the help of state-of-the-art Faddeev calculations.

  5. NUSTAR, SWIFT, and GROND Observations of the Flaring MEV Blazar PMN J0641-0320

    DEFF Research Database (Denmark)

    Ajello, M.; Ghisellini, G.; Paliya, V. S.

    2016-01-01

    Area Telescope and subsequent follow-up observations with NuSTAR, Swift, and GROND of a new member of the MeV blazar family: PMN J0641-0320. Our optical spectroscopy provides confirmation that this is a flat-spectrum radio quasar located at a redshift of z = 1.196. Its very hard NuSTAR spectrum (power......-law photon index of similar to 1 up to similar to 80 keV) indicates that the emission is produced via inverse Compton scattering off of photons coming from outside the jet. The overall spectral energy distribution of PMN J0641-0320 is typical of powerful blazars and, using a simple one-zone leptonic emission...... model, we infer that the emission region is located either inside the broad line region or within the dusty torus....

  6. Capacitance and conductance studies on silicon solar cells subjected to 8 MeV electron irradiations

    Science.gov (United States)

    Sathyanarayana Bhat, P.; Rao, Asha; Sanjeev, Ganesh; Usha, G.; Priya, G. Krishna; Sankaran, M.; Puthanveettil, Suresh E.

    2015-06-01

    The space grade silicon solar cells were irradiated with 8 MeV electrons with doses ranging from 5-100 k Gy. Capacitance and conductance measurements were carried out in order to investigate the anomalous degradation of the cells in the radiation harsh environments and the results are presented in this paper. Detailed and systematic analysis of the frequency-dependent capacitance and conductance measurements were performed to extract the information about the interface trap states. The small increase in density of interface states was observed from the conductance-frequency measurements. The reduction in carrier concentration upon electron irradiation is due to the trapping of charge carriers by the radiation induced trap centres. The Drive Level Capacitance Profiling (DLCP) technique has been applied to study the properties of defects in silicon solar cells. A small variation in responding state densities with measuring frequency was observed and the defect densities are in the range 1015 -1016 cm-3.

  7. Disintegration of {sup 12}C nuclei by 700–1500 MeV photons

    Energy Technology Data Exchange (ETDEWEB)

    Nedorezov, V. [Institute for Nuclear Research, Russian Academy of Sciences, Prospekt 60-letiya Oktyabrya 7a, 117312 Moscow (Russian Federation); D' Angelo, A.; Bartalini, O. [Dipartimento di Fisica – Università degli Studi di Roma “Tor Vergata”, via della Ricerca Scientifica 1, I-00133 Roma (Italy); INFN – Sezione di Roma “Tor Vergata”, via della Ricerca Scientifica 1, I-00133 Roma (Italy); Bellini, V. [Dipartimento di Fisica – Università degli Studi di Catania, via Santa Sofia 64, I-95123 Catania (Italy); INFN – Sezione di Catania, via Santa Sofia 64, I-95123 Catania (Italy); Capogni, M. [Dipartimento di Fisica – Università degli Studi di Roma “Tor Vergata”, via della Ricerca Scientifica 1, I-00133 Roma (Italy); INFN – Sezione di Roma “Tor Vergata”, via della Ricerca Scientifica 1, I-00133 Roma (Italy); Casano, L.E. [INFN – Sezione di Roma “Tor Vergata”, via della Ricerca Scientifica 1, I-00133 Roma (Italy); Castoldi, M. [Dipartimento di Fisica – Università degli Studi di Genova, via Dodecaneso 33, I-16146 Genova (Italy); Curciarello, F.; De Leo, V. [Dipartimento di Fisica e di Scienze della Terra, Università di Messina, salita Sperone 31, I-98166 Messina (Italy); INFN – Sezione di Catania, via Santa Sofia 64, I-95123 Catania (Italy); Didelez, J.-P. [IN2P3, Institut de Physique Nucléaire, Rue Georges Clemenceau, F-91406 Orsay (France); and others

    2015-08-15

    Disintegration of {sup 12}C nuclei by tagged photons of 700–1500 MeV energy at the GRAAL facility has been studied by means of the LAGRANγE detector with a wide angular acceptance. The energy and momentum distributions of produced neutrons and protons as well as their multiplicity distributions were measured and compared with corresponding distributions calculated with the RELDIS model based on the intranuclear cascade and Fermi break-up models. It was found that eight fragments are created on average once per about 100 disintegration events, while a complete fragmentation of {sup 12}C into 12 nucleons is observed typically only once per 2000 events. Measured multiplicity distributions of produced fragments are well described by the model. The measured total photoabsorption cross section on {sup 12}C in the same energy range is also reported.

  8. 520 MeV proton irradiation effects on GaAs/Ge space solar cells

    CERN Document Server

    Wang Rong; Guo Zeng Liang; Zhang Xin; Zhai Zuo Xu

    2002-01-01

    High-energy proton irradiation effects on GaAs/Ge solar cells for space use are studied. The cells are irradiated by protons with an energy of 5-20 MeV up to a fluence ranging from 1 x 10 sup 9 to 7 x 10 sup 1 sup 3 cm sup - sup 2 , and then the change of the photovoltaic performances is measured at AMO. It is shown that the performances of the cells keep no change under 1 x 10 sup 9 cm sup - sup 2 irradiation. Above 1 x 10 sup 9 cm sup - sup 2 irradiation, I sub s sub c , V sub o sub c and P sub m sub a sub x degrade, as proton irradiation fluence increases. But the higher the proton energy, the less the degradation of I sub s sub c , V sub o sub c and P sub m sub a sub x

  9. Calculation of Multisphere Neutron Spectrometer Response Functions in Energy Range up to 20 MeV

    CERN Document Server

    Martinkovic, J

    2005-01-01

    Multisphere neutron spectrometer is a basic instrument of neutron measurements in the scattered radiation field at charged-particles accelerators for radiation protection and dosimetry purposes. The precise calculation of the spectrometer response functions is a necessary condition of the propriety of neutron spectra unfolding. The results of the response functions calculation for the JINR spectrometer with LiI(Eu) detector (a set of 6 homogeneous and 1 heterogeneous moderators, "bare" detector within cadmium cover and without it) at two geometries of the spectrometer irradiation - in uniform monodirectional and uniform isotropic neutron fields - are given. The calculation was carried out by the code MCNP in the neutron energy range 10$^{-8}$-20 MeV.

  10. Spallation yield of neutrons produced in thick lead target bombarded with 250 MeV protons

    Science.gov (United States)

    Chen, L.; Ma, F.; Zhanga, X. Y.; Ju, Y. Q.; Zhang, H. B.; Ge, H. L.; Wang, J. G.; Zhou, B.; Li, Y. Y.; Xu, X. W.; Luo, P.; Yang, L.; Zhang, Y. B.; Li, J. Y.; Xu, J. K.; Liang, T. J.; Wang, S. L.; Yang, Y. W.; Gu, L.

    2015-01-01

    The neutron yield from thick target of Pb irradiated with 250 MeV protons has been studied experimentally. The neutron production was measured with the water-bath gold method. The thermal neutron distributions in the water were determined according to the measured activities of Au foils. Corresponding results calculated with the Monte Carlo code MCNPX were compared with the experimental data. It was found out that the Au foils with cadmium cover significantly changed the spacial distribution of the thermal neutron field. The corrected neutron yield was deduced to be 2.23 ± 0.19 n/proton by considering the influence of the Cd cover on the thermal neutron flux.

  11. Nuclear physics research program at the 30 MeV Karaj cyclotron

    CERN Document Server

    Noshad, H; Lamehi-Rachti, M; Talebi-Taher, A R; Aslani, G; Maboudi-Moghaddam, S; Rahighi, J; Kakuee, O R; Heydari, N

    2002-01-01

    A versatile reaction chamber and its accessories as well as a multiparameter data acquisition system were designed, assembled, and installed in the R and D hall at NRCAM to allow nuclear measurements. The sup 2 sup 0 sup 9 Bi(p,f) and sup 1 sup 9 sup 7 Au(p,f) reaction experiments at E sub p =30 MeV were performed. The good agreement between our experimental results as compared with previously published data are presented here to show the reliability of our apparatus. In the case of the bismuth reaction, the fission cross section obtained by using pair spectrometry as well as its associated error have been measured for the first time.

  12. 42 MeV bremsstrahlung spectrum analysis by a photoactivation method

    Energy Technology Data Exchange (ETDEWEB)

    Calzado, A.; Vano, E.; Delgado, V.; Gonzalez, L. (Universidad Complutense de Madrid (Spain). Catedra de Fisica Medica; Junta de Energia Nuclear, Madrid (Spain). Inst. de Estudios Nucleares)

    1984-08-01

    The evaluation of 42 MeV, bremsstrahlung spectra from a clinical betatron by using the photoactivation method is described. Photonuclear reactions, mainly of the (..gamma.., n) type, are used as activation detectors. After measurements of photon-induced activities from residual nuclei are performed, the spectral distribution of photons is evaluated by solving the unfolding problem. The latter is carried out through the use of two independent methods, orthonormal expansion and Monte Carlo. In both cases prior conditions to the solution are imposed. Spectra evaluated by both methods and making use of two different size flattening filters are presented. An empirical method to estimate the 'effective' thickness of the Pt target is described.

  13. Turbulent transport of MeV range cyclotron heated minorities as compared to alpha particles

    CERN Document Server

    Pusztai, István; Kazakov, Yevgen O; Fülöp, Tünde

    2016-01-01

    We study the turbulent transport of an ion cyclotron resonance heated (ICRH), MeV range minority ion species in tokamak plasmas. Such highly energetic minorities, which can be produced in the three ion minority heating scheme [Ye. O. Kazakov et al. (2015) Nucl. Fusion 55, 032001], have been proposed to be used to experimentally study the confinement properties of fast ions without the generation of fusion alphas. We compare the turbulent transport properties of ICRH ions with that of fusion born alpha particles. Our results indicate that care must be taken when conclusions are drawn from experimental results: While the effect of turbulence on these particles is similar in terms of transport coefficients, differences in their distribution functions - ultimately their generation processes - make the resulting turbulent fluxes different.

  14. MeV Neutron Production from Thermal Neutron Capture in 6Li Simulated With Geant4

    Science.gov (United States)

    Santoro, Valentina; DiJulio, Douglas D.; Bentley, Phillip M.

    2016-09-01

    Various Li compounds are commonly used at neutron facilities as neutron absorbers. These compounds provide one of the highest ratios of neutron attenuation to y- ray production. Unfortunately, the usage of these compounds can also give rise to fast neutron emission with energies up to almost 16 MeV. Historically, some details in this fast neutron production mechanism can be absent from some modeling packages under some optimization scenarios. In this work, we tested Geant4 to assess the performance of this simulation toolkit for the fast neutron generation mechanism. We compare the results of simulations performed with Geant4 to available measurements. The outcome of our study shows that results of the Geant4 simulations are in good agreement with the available measurements for 6 Li fast neutron production, and suitable for neutron instrument background evaluation at spallation neutron sources.

  15. Response of CVD Diamond Detectors to 14 MeV Neutrons

    CERN Document Server

    Weiss, C; Gagnon-Moisan, F; Kasper, A; Lucke, A; Schuhmacher, H; Weierganz, M; Zimba, A

    2012-01-01

    A series of measurements was taken at the Physikalisch-Technische Bundesanstalt (PTB) Braunschweig [1] using the 14 MeV neutron beam at the Van der Graaf accelerator with chemical vapor deposition (CVD) diamond detectors, in preparation of an upcoming (n, ) cross-section measurement [2] at the CERN-n TOF experiment [3, 4]. A single-crystal (sCVD) as well as a poly-crystalline (pCVD) diamond detector were used for the measurements. The response of both materials to the mono-energetic neutron beam was studied, also with the prospect for future applications in plasma diagnostics for fusion research. The results of the measurements are presented in this report.

  16. Titanium-II: an evaluated nuclear data file. [E < 20. 0 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Philis, C.; Howerton, R.; Smith, A.B.

    1977-06-01

    A comprehensive evaluated nuclear data file for elemental titanium is outlined including definition of the data base, the evaluation procedures and judgments, and the final evaluated results. The file describes all significant neutron-induced reactions with elemental titanium and the associated photon-production processes to incident neutron energies of 20.0 MeV. In addition, isotopic-reaction files, consistent with the elemental file, are separately defined for those processes which are important to applied considerations of material-damage and neutron-dosimetry. The file is formulated in the ENDF format. This report formally documents the evaluation and, together with the numerical file, is submitted for consideration as a part of the ENDF/B-V evaluated file system. 20 figures, 9 tables.

  17. Elastic and inelastic scattering of 50-MeV pions from 28Si and 30Si

    Science.gov (United States)

    Wienands, U.; Hessey, N.; Barnett, B. M.; Rozon, F. M.; Roser, H. W.; Altman, A.; Johnson, R. R.; Gill, D. R.; Smith, G. R.; Wiedner, C. A.; Manley, D. M.; Berman, B. L.; Crawford, H. J.; Grion, N.

    1987-02-01

    Angular distributions of the differential cross section for elastic and inelastic scattering of 50-MeV π+ and π- on 28Si and 30Si have been measured to a relative accuracy of 5-10 We fitted the cross section of elastic π+ and π- scattering from 28Si simultaneously with an optical model using a second-order potential of the Michigan State University form. Our best-fit parameters differ from those given previously. The ratio of the neutron and proton transition-matrix elements for the first Jπ=2+ state in 28Si is found from the inelastic cross section to be 1.13+/-0.09. For 30Si, the ratio is found to be 0.93+/-0.09, which differs significantly from the value derived from lifetime measurements on mirror nuclei.

  18. Bunch evolution study in optimization of MeV ultrafast electron diffraction

    Science.gov (United States)

    Lu, Xian-Hai; Du, Ying-Chao; Huang, Wen-Hui; Tang, Chuan-Xiang

    2014-12-01

    Megaelectronvolt ultrafast electron diffraction (UED) is a promising detection tool for ultrafast processes. The quality of diffraction image is determined by the transverse evolution of the probe bunch. In this paper, we study the contributing terms of the emittance and space charge effects to the bunch evolution in the MeV UED scheme, employing a mean-field model with an ellipsoidal distribution as well as particle tracking simulation. The small transverse dimension of the drive laser is found to be critical to improve the reciprocal resolution, exploiting both smaller emittance and larger transverse bunch size before the solenoid. The degradation of the reciprocal spatial resolution caused by the space charge effects should be carefully controlled.

  19. Single-shot MeV transmission electron microscopy with picosecond temporal resolution

    CERN Document Server

    Li, R K

    2014-01-01

    Pushing the limits in temporal resolution for transmission electron microscopy (TEM) requires a revolutionary change in the electron source technology. In this paper we study the possibility of employing a radiofrequency photoinjector as the electron source for a time-resolved TEM. By raising the beam energy to the relativistic regime we minimize the space charge effects which otherwise limit the spatio-temporal resolution of the instrument. Analysis and optimization of the system taking into account the achievable beam brightness, electron flux on the sample, chromatic and spherical aberration of the electron optic system, and space charge effects in image formation are presented and supported by detailed numerical modeling. The results demonstrate the feasibility of 10 nanometer - 10 picosecond spatio-temporal resolution single-shot MeV TEM.

  20. Transmission secondary ion mass spectrometry using 5 MeV C60+ ions

    Science.gov (United States)

    Nakajima, K.; Nagano, K.; Suzuki, M.; Narumi, K.; Saitoh, Y.; Hirata, K.; Kimura, K.

    2014-03-01

    In the secondary ion mass spectrometry (SIMS), use of cluster ions has an advantage of producing a high sensitivity of intact large molecular ions over monatomic ions. This paper presents further yield enhancement of the intact biomolecular ions by measuring the secondary ions emitted in the forward direction. Phenylalanine amino acid films deposited on self-supporting thin Si3N4 films were bombarded with 5 MeV C60 ions. Secondary ions emitted in the forward and backward directions were measured. The yield of intact phenylalanine molecular ions emitted in the forward direction is significantly enhanced compared to the backward direction while fragment ions are suppressed. This suggests a large potential of using transmission cluster ion SIMS for the analysis of biological materials.