Download or read book Neutron proton Bremsstrahlung Experiments written by and published by . This book was released on 1992 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is well known that charged particles emit bremsstrahlung radiation when they are accelerated. Classical electron bremsstrahlung occurs when a photon is emitted by an electron accelerated in the field of a nucleus. The bremsstrahlung process also occurs in the scattering of nucleons, for which it is the lowest energy inelastic process that can occur. Like electron bremsstrahlung, nucleon-nucleon bremsstrahlung also requires the exchange of a virtual particle to conserve energy and momentum. In electron bremsstrahlung a virtual photon is exchanged but with two nucleons a meson can be exchanged. Unlike electron bremsstrahlung, in nucleon-nucleon bremsstrahlung the photon can originate from the exchanged meson. This exchange contribution has been shown in calculations to be a significant fraction of bremsstrahlung events. Thus bremsstrahlung serves as a probe of exchange currents in the nucleon-nucleon interaction. Because of a lack of a free neutron target or an intense neutron beam, few measurements of neutron-proton bremsstrahlung exist, each having poor statistical accuracy and poor energy resolution. The white neutron source at the Weapons Neutron Research (WNR) target area at the Los Alamos Meson Physics Facility (LAMPF) produces neutrons with energies from below 50 to above 400 MeV. Using time-of-flight techniques and a liquid hydrogen target, we are measuring the outgoing photons of energies up to 250 MeV at gamma ray angles of around 90[degree] relative to the incident beam. Protons scattered at very forward angles are also detected in coincidence with the gamma rays.
Download or read book Possibilities for a Neutron proton Bremsstrahlung Experiment at WNR written by and published by . This book was released on 1990 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The high energy and high intensity of the continuous energy (white) neutron source at the WNR target area of the Los alamos Meson Physics Facility (LAMPF) may make possible a direct measurement of the neutron-proton bremsstrahlung (NPB) cross section. Several recent papers have discussed the operation of the WNR white neutron source in detail so we will just include a short description of the relevant properties of the source in this article. Next we will describe one possible method of measuring the NPB cross section which is based on two calorimetric detectors that measure the energies of the scattered neutrons and the recoil protons. There are several advantages in using a white neutron source for this type of measurement. First, a wide range of incident neutron energies may be covered. In the case of the WNR, the energy range is from below 50 MeV to over 400 MeV which is above the pion production threshold. Second, all incident neutron energies are measured simultaneously. The greatly reduces the systematic errors associated with sequential measurements at different beam energies when measuring the energy dependence of the NPB cross section. Third, the neutron beam is shared amongst several experimenters at WNR. This greatly reduces the competition for beam time, so longer runs are often possible compared to facilities that require the dedicated use of the accelerator. In the past, typical experiments have run for several months. 6 refs., 5 figs.
Download or read book Neutron proton Bremsstrahlung Studies Using the White Neutron Source at the LAMPF written by and published by . This book was released on 1990 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nucleon-nucleon bremsstrahlung is a few-body radiative process that provides insight into several areas of nuclear physics. It is one of the simplest systems for studying the off-shell behavior of the nucleon-nucleon potential. The physics involved in neutron-proton bremsstrahlung (NPB) is significantly different from that of proton-proton bremsstrahlung (PPB). In particular, NPB cross sections are much larger than PPB cross sections because NPB allows E1 radiation, and the contribution to the cross section from the meson exchange currents has been calculated to be as large as the contributions from external radiation. To date there have been essentially four NPB experiments. These measurements have covered only a small part of the available phase space. A major experimental problem in performing these measurements has been the lack of a suitable intense, high-energy neutron beam. We are planning a measurement of the NPB cross section using the white neutron source at the WNR target area at the LAMPF accelerator. We plant to implement the experiment in three phases. In this first state, we shall measure inclusive hard-photon production using a multi-element gamma-ray telescope that is insensitive to neutrons. In the second phase, we shall measure the bremsstrahlung gamma-rays in coincidence with recoil protons. In the last phase, we shall detect the scattered neutrons in coincidence with the recoil protons and gamma rays. 8 refs., 6 figs.
Download or read book Neutron proton Bremsstrahlung Inclusive Photon Measurements from 100 to 280 MeV written by Douglas Ray Mayo and published by . This book was released on 1997 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Energy Bremsstrahlung from Proton nucleus Collisions written by Walter Carl Beckham and published by . This book was released on 1962 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lectures from the Workshop on Nucleon Nucleon Bremsstrahlung January 25 26 1990 written by Clinton P. Anderson Meson Physics Facility and published by . This book was released on 1990 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Proton Bremsstrahlung written by Yaşar Safkan and published by . This book was released on 2001 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: The triply-differential cross section for neutron-proton bremsstrahlung (np -+ np[gamma]) was measured at the WNR facility of Los Alamos National Laboratory. A liquid hydrogen target was exposed to the pulsed neutron beam, and the scattered neutrons and recoil protons were observed in coincidence at angles of 20°, 28°, and 36° on opposite sides of the beam. Measuring the proton and neutron energies allows the reconstruction of the full kinematics for each event. Events with incident neutron energies between 175 and 275 MeV are included in the data analysis so as to remain below the pion production threshold. The resulting photon angular distributions for each of the nine angle pairs are presented, and are compared with theoretical predictions.
Download or read book A Measurement of Neutron proton Bremsstrahlung Near 130 MeV written by J.A. Edgington and published by . This book was released on 1973 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron proton Bremsstrahlung at 4 8 MeV written by John Whittaker and published by . This book was released on 1979* with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book ASYMMETRIC NEUTRON PROTON BREMSSTRAHLUNG AT 130 MeV written by and published by . This book was released on 1972 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proton Therapy Physics written by Harald Paganetti and published by CRC Press. This book was released on 2016-04-19 with total page 691 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proton Therapy Physics goes beyond current books on proton therapy to provide an in-depth overview of the physics aspects of this radiation therapy modality, eliminating the need to dig through information scattered in the medical physics literature. After tracing the history of proton therapy, the book summarizes the atomic and nuclear physics background necessary for understanding proton interactions with tissue. It describes the physics of proton accelerators, the parameters of clinical proton beams, and the mechanisms to generate a conformal dose distribution in a patient. The text then covers detector systems and measuring techniques for reference dosimetry, outlines basic quality assurance and commissioning guidelines, and gives examples of Monte Carlo simulations in proton therapy. The book moves on to discussions of treatment planning for single- and multiple-field uniform doses, dose calculation concepts and algorithms, and precision and uncertainties for nonmoving and moving targets. It also examines computerized treatment plan optimization, methods for in vivo dose or beam range verification, the safety of patients and operating personnel, and the biological implications of using protons from a physics perspective. The final chapter illustrates the use of risk models for common tissue complications in treatment optimization. Along with exploring quality assurance issues and biological considerations, this practical guide collects the latest clinical studies on the use of protons in treatment planning and radiation monitoring. Suitable for both newcomers in medical physics and more seasoned specialists in radiation oncology, the book helps readers understand the uncertainties and limitations of precisely shaped dose distribution.
Download or read book High Energy Bremsstrahlung from Proton neutron Collisions written by Walter Carl Beckham and published by . This book was released on 1962 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Preliminary Report on a Neutron proton Scattering Experiment written by Charles L. Storrs and published by . This book was released on 1949 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron proton Scattering Experiments Near 50 MeV written by C. J. Batty and published by . This book was released on 1965 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bremsstrahlung from Proton Bombardment of Nuclei written by Daṿid ben Yosef Kohen and published by . This book was released on 1956 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:
