Download or read book Compendium of Neutron Beam Facilities for High Precision Nuclear Data Measurements written by International Atomic Energy Agency and published by International Atomic Energy Agency. This book was released on 2014-09-18 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: The IAEA organized and coordinated the technical meeting Use of Neutron Beams for High Precision Nuclear Data Measurements, in Budapest, Hungary, 1014 December 2012. The objectives of the meeting were to provide a forum to exchange existing know-how and to share the practical experiences of neutron beam facilities and associated instrumentation, with regard to the measurement of high precision nuclear data using both accelerators and research reactors. Furthermore, the present status and future developments of worldwide accelerator and research reactor based neutron beam facilities were discussed.
Download or read book The N TOF Facility Neutron Beams for Challenging Future Measurements at CERN written by Enrico Chiaveri and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The CERN n_TOF neutron beam facility is characterized by a very high instantaneous neutron flux, excellent TOF resolution at the 185)m long flight path (EAR-1), low intrinsic background and coverage of a wide range of neutron energies, from thermal to a few GeV. These characteristics provide a unique possibility to perform high-accuracy measurements of neutron-induced reaction cross-sections and angular distributions of interest for fundamental and applied Nuclear Physics. Since 2001, the n_TOF Collaboration has collected a wealth of high quality nuclear data relevant for nuclear astrophysics, nuclear reactor technology, nuclear medicine, etc. The overall efficiency of the experimental program and the range of possible measurements has been expanded with the construction of a second experimental area (EAR-2), located 20)m on the vertical of the n_TOF spallation target. This upgrade, which benefits from a neutron flux 30 times higher than in EAR-1, provides a substantial extension in measurement capabilities, opening the possibility to collect data on neutron cross-section of isotopes with short half-lives or available in very small amounts. This contribution will outline the main characteristics of the n_TOF facility, with special emphasis on the new experimental area. In particular, we will discuss the innovative features of the EAR-2 neutron beam that make possible to perform very challenging measurements on short-lived radioisotopes or sub-mg samples, out of reach up to now at other neutron facilities around the world. Finally, the future perspectives of the facility will be presented.
Download or read book Neutron Beam Design Development and Performance for Neutron Capture Therapy written by Otto K. Harling and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: For this Workshop, the organizers have attempted to invite experts from all known centers which are engaged in neutron beam development for neutron capture therapy. The Workshop was designed around a series of nineteen invited papers which dealt with neutron source design and development and beam characterization and performance. Emphasis was placed on epithermal beams because they offer clinical advantages and are more challenging to implement than thermal beams. Fission reactor sources were the basis for the majority of the papers; however three papers dealt with accelerator neutron sources. An additional three invited papers provided a summary of clinical results of Ncr therapy in Japan between 1968 and 1989 and overviews of clinical considerations for neutron capture therapy and of the status of tumor targeting chemical agents for Ncr. Five contributed poster papers dealing with NCT beam design and performance were also presented. A rapporteurs' paper was prepared after the Workshop to attempt to summarize the major aspects, issues, and conclusions which resulted from this Workshop. Many people contributed to both the smooth functioning of the Workshop and to the preparation of these proceedings. Special thanks are reserved for Ms. Dorothy K.
Download or read book Fundamental Physics with Pulsed Neutron Beams written by Christopher R. Gould and published by World Scientific. This book was released on 2001 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low energy neutron beams are used to address many questions in nuclear physics, particle physics and astrophysics. The scientific issues include elucidating the nature of time reversal noninvariance; understanding the origin of the baryon asymmetry in the Universe; describing the weak interaction between quarks and between nucleons; understanding the origin of the elements in stellar and big bang nucleosynthesis.This book summarizes how spallation neutron sources work and discuss the advantages of pulsed beams in reducing systematic errors in precision measurements. It also describes recent breakthroughs in ultracold neutron production, together with the physics that will be addressed by the new generation of intense neutron sources.
Download or read book Current Status of Neutron Scattering Research and Facilities in the United States written by National Research Council and published by National Academies Press. This book was released on 1984-02-01 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development and Applications of Residual Stress Measurements Using Neutron Beams written by International Atomic Energy Agency and published by . This book was released on 2014 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication is the result of an IAEA coordinated research project and presents a survey of the basic principles, requirements, preparation, design, execution and standardisation of residual stress measurements using neutron beams. It includes details of experimental techniques, associated equipment and instrumentation, their commissioning and calibration, control and data acquisition. A separate chapter is dedicated to data analysis and interpretation. At the end, the document provides, with a number of selected examples, applications of residual stress measurements as well as future trends for development and use of this powerful technique. The publication is a comprehensive and useful resource to the neutron beam user community including academia and industrial partners. It may serve as an introduction to the field for young researchers and graduate students as well as guidelines to those operating or planning to implement/modernise their facilities for residual stress measurements. Ultimately, the document presents neutron beams as a valuable and effective tool for performing residual stress measurements both for basic research and various applications.
Download or read book Experimental Neutron Scattering written by Bertram Terence Martin Willis and published by Oxford University Press. This book was released on 2009-03-19 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a broad survey of the work carried out by scientists at neutron centres around the world, which provide the facilities for generating intense beams of neutrons.These beams are essential in investigating the atomic structures of a wide range of materials such as magnetic alloys, superconductors, polymers, or proteins.
Download or read book Proposals on RENDA written by L.N. Usachev and published by . This book was released on 1972 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics and Radiobiology of Fast Neutron Beams written by David K. Bewley and published by CRC Press. This book was released on 1989-10-01 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over fifty years have passed since the first patient was treated with fast neutrons, but this form of therapy is still a matter of bitter dispute. Neutron generators have been installed in many countries and now patients can be treated with equipment that is technically similar to modern megavoltage x-ray equipment. The Physics and Radiobiology of Fast Neutron Beams presents a full discussion of the physical and radiobiological factors governing the production and use of fast neutron beams for therapy. The book discusses vastly improved neutron generators, advances in the standardization of dosimetric methods, and the specification of radiation quality. In addition, it explores nuclear methods of analysis, particularly neutron activation analysis in vivo. Influencing the place of radiotherapy with neutrons and other heavy particles, the radiobiological factors governing the treatment of cancer with radiation are examined. The author also studies the radiation hazard of neutrons, a matter of importance in the use of neutrons for chemical analysis in vivo. The Physics and Radiobiology of Fast Neutron Beams will be a valuable introduction to the subject for radiotherapists, medical physicists, radiographers, and radiobiologists new to the field. The book is also a useful summary of current knowledge for those already established in the use of fast neutrons for medical purposes.
Download or read book Facilities for High intensity Neutron Irradiation written by Jerry B. Marion and published by . This book was released on 1966 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: An analysis is made of the possibilities of producing high-intensity beams of neutrons with energies other than 14 MeV. It appears that the 3-MV accelerators which are likely to be available within the next few years will be capable of delivering beams of charged particles with currents up to about 15 mA. With this beam limitation it will not be possible to deliver a sample irradiation flux of more than 10 to the 11th power neutrons/sec, if monoenergetic neutrons are required. On the other hand, present capabilities of higher energy accelerators (e.g., 100-MeV cyclotrons) will permit the generation of approximately 10 to the 15th neutrons/sec. Since the majority of these neutrons are emitted into a very narrow forward cone, it would be possible to utilize almost the entire neutron output for irradiation purposes. For biological studies in which the maximum possible neutron flux is required, it appears that an accelerator which will yield beam energies considerably in excess of 3 MeV will be required.
Download or read book Use of Neutron Beams for Materials Research Relevant to the Nuclear Energy Sector written by International Atomic Energy Agency and published by . This book was released on 2015 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This publication is a compilation of the main results and findings of an IAEA coordinated research project (CRP) on development, characterization and testing of materials of relevance to nuclear energy sector using neutron beams. The document contains joint research results from nineteen institutions, which can be grouped into the main six technical areas: investigation of oxide dispersion-strengthened steels, research on zirconium based materials (including hydrogen uptake), investigations of welded structures and objects, results with irradiated materials, optimization of instruments for residual strain/stress measurements, and efforts towards standardization of neutron imaging. Particular emphasis was placed on variable environments during material characterization and testing as required by some applications such as intensive irradiation load, high temperature and high pressure conditions, and the presence of strong magnetic fields. The publication also includes some additional materials supplied by the international experts along with nineteen individual contributions describing the current status of use of diverse neutron beam techniques for materials research targeting the nuclear energy sector. These nineteen individual reports are available on CD-ROM attached to this publication. The publication will be of interest to physicists and engineers in the area of materials research, neutron beam scientists and personnel responsible for instruments, managers of neutron beam facilities, nuclear reactor designers and nuclear industry representatives."--Publisher's description.
Download or read book Neutron physics and nuclear data measurements with accelerators and research reactors written by and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Physics and Nuclear Data Measurements with Accelerators and Research Reactors written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Nuclear Data Compilation and Evaluation written by Josef J. Schmidt and published by . This book was released on 1969 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance of a New Composite Single Crystal Filtered Thermal Neutron Beam for Neutron Capture Therapy Research at the University of Missouri written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The University of Missouri (MU) Institute for Nano and Molecular Medicine, the Idaho National Laboratory (INL) and the University of Missouri Research Reactor (MURR) have undertaken a new collaborative research initiative to further the development of improved boron delivery agents for BNCT. The first step of this effort has involved the design and construction of a new thermal neutron beam irradiation facility for cell and small-animal radiobological research at the MURR. In this paper we present the beamline design with the results of pertinent neutronic design calculations. Results of neutronic performance measurements, initiated in February 2008, will also be available for inclusion in the final paper. The new beam will be located in an existing 152.4 mm (6') diameter MURR beam tube extending from the core to the right in Figure 1. The neutron beam that emanates from the berylium reflector around the reactor is filtered with single-crystal silicon and single-crystal bismuth segments to remove high energy, fission spectrum neutrons and reactor gamma ray contamination. The irradiation chamber is downstream of the bismuth filter section, and approximately 3.95 m from the central axis of the reactor. There is sufficient neutron flux available from the MURR at its rated power of 10 MW to avoid the need for cryogenic cooling of the crystals. The MURR operates on average 150 hours per week, 52 weeks a year. In order to take advantage of 7800 hours of operation time per year the small animal BNCT facility will incorparate a shutter constucuted of boral, lead, steel and polyethylene that will allow experimenters to access the irradiation chamber a few minutes after irradiation. Independent deterministic and stochastic models of the coupled reactor core and beamline were developed using the DORT two-dimensional radiation transport code and the MCNP-5 Monte Carlo code, respectively. The BUGLE-80 47-neutron, 20-gamma group cross section library was employed for the DORT computations, in keeping with previous practice for analysis of a number of other NCT neutron facilities worldwide. The standard ENDF/B Version 6.8 cross section libraries were used with MCNP, except that special calculated cross section sets for the single-crystal bismuth and silicon filters in the MCNP calculations were provided to MU and INL specifically for this study by the Korean Atomic Energy Research Institute and, independently, by North Carolina State University. Cross sections for the amorphous bismuth and silicon files on the BUGLE-80 library used with DORT were modified to account for the single-crystal form of these materials using correction factors computed using MCNP. A number of parameter studies were conducted, independently varying the thicknesses of the silicon and bismuth filter sections to find an optimum that maximizes the thermal neutron flux while maintaining the fast-neutron and gamma components of the beam within acceptable ranges. Both the DORT and MCNP beamline optimization computations led to the conclusion that the silicon filtering section should be approximately 55 cm in thickness and the bismuth section should be 8 cm in thickness. The total estimated thermal neutron flux delivered to the irradiation location by the filtered beam, integrated to 0.414 eV, is approximately 9.0 x 108 neutrons/cm2-s. The calculations also yielded an epithermal and fast-neutron kerma of approximately 1.0 x 10-11 cGy-cm2.
Download or read book Detailed Beta decay Studies of Neutron rich 74 77Ga Isotopes written by Umesh Silwal and published by . This book was released on 2018 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: The National Nuclear Data Center (NNDC) contains a compilation of information on the beta decays of Gallium isotopes. In the mass range A = 74 to 77, the Germanium daughters lie close to or at the valley of stability leading us to believe the decays would have been well studied. However, closer inspection indicates significant conflict for placement of gamma-rays and energy levels between different measurements, especially for upper-lying states. Detailed beta-decay studies for the 74−77Ga isotopes were performed using a high resolution four clover Hyper-Pure Germanium (HPGe) detector system with two beta scintillators in the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Lab (ORNL) to better understand the structure of the corresponding 74−77Ge daughter nuclei. In our experiments, use of a high-resolution mass separator greatly improved the purity of the samples in comparison to previous measurements. Besides that, the efficiency of the detector system we utilized was much higher than used in previous studies. We also established a method to determine statistically significant gamma-gamma coincidence relationships to add reliability to the placement of gamma rays to energy levels and avoid experimental biases. From our analysis, we have established comprehensive decay schemes for all four Germanium nuclei in this study. In most cases, we have extended the energy levels to cover more of the energy window available for beta decay. Our proposed 74Ge decay scheme contains 44 energy levels occupying up to 4.36 MeV with the placement of 99 gamma rays. Similarly, 75Ga decay scheme contains 71 gamma rays with 30 energy levels occupying up to 2.75 MeV. The 76Ga decay scheme has 48 excited states with 100 gamma rays occupying up to 4.81 MeV. And, the 77Ge decay scheme has 67 gamma rays and 33 energy levels occupying up to 3.14 MeV. Based on the expanded level schemes, beta-feeding intensity and log (ft) value lower limits were calculated and attempts were made to assign the spin-parity of the observed states. The resulting level schemes were then compared with the Nushellx theoretical predictions.
Download or read book Nuclear Data for Science and Technology written by Syed M. Qaim and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1041 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the Proceedings of the International Conference on Nuclear Data for Science and Technology held at Jillich in May 1991. The conference was in a series of application oriented nuclear data conferences organized in the past under the auspices of the Nuclear Energy Agency-Nuclear Data Committee (NEANDC) and with the support of the Nuclear Energy Agency-Committee on Reactor Physics (NEACRP). It was the fIrst international conference on nuclear data held in Germany, with the scientific responsibility entrusted to the Institute of Nuclear Chemistry of the Research Centre Jillich. The scientific programme was established by the International Programme Committee in consultation with the International Advisers, and the NEA and IAEA cooperated in the organization. A total of 328 persons from 37 countries and fIve international organizations participated. The scope of these Proceedings extends to a wide range of interdisciplinary topics dealing with measu rement, calculation, evaluation and application of nuclear data, with a major emphasis on numerical data. Both energy and non-energy related applications are considered and due attention is given to some fundamental aspects relevant to the understanding of nuclear data.
