Download or read book Neutron Yields from Proton Bombardment of Thick Targets written by Thomas Marshall Amos (Jr.) and published by . This book was released on 1972 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Yields from Thick Targets Bombarded by 18 and 32 Mev Protons written by George Patrick Millburn and published by . This book was released on 1956 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Relative High Energy Neutron Yields from Targets Bombarded with Protons and Deuterons UCRL 440 written by William J. Knox and published by . This book was released on 1950 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Relative neutron yields in the forward direction from various target elements bombarded with 350 Mev protons and 190 Mev deuterons have been measured. Bismuth fission chambers with a threshold of about 50 Mev were used to detect the high energy neutrons. The actual flux of protons or deuterons traversing each target was determined from the activities induced in graphite monitors attached to the target. When a deuteron beam is used, the neutron yields for light elements agree with the values predicted by the deuteron stripping theory. For the heavy elements the observed values are fitted best by adding a function proportional to Z-sq to the stripping theory values. This may be interpreted as evidence for the production of high energy neutrons by the electric field disintegration of the deuteron. The neutron yields from the proton beam vary approximately as (A - Z)(exp(2/3)) for target elements from C to U. This indicates that the heavy elements are not completely transparent to 350 Mev protons. Beryllium has an anomalous neutron yield 50% higher than that for C. Calculations and measurements on the problem of multiple traversals of beam particles through thin targets are presented.
Download or read book Thick target Neutron and gamma ray Yields Induced by Medium energy Proton and Deuteron Bombardments written by Lawrence Livermore Laboratory and published by . This book was released on 1979 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron yields from high energy heavy ion bombardment of thick heavy targets written by G. C. Ball and published by . This book was released on 1981 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thick target neutron and ray yields induced by medium energy proton and deuteron bombardments written by Lawrence Livermore Laboratory and published by . This book was released on 1979 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Angular Distributions and Spectra Produced by the Bombardment of Thick Targets by Deuterons written by C. E. Falk and published by . This book was released on 1950 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thick Target Neutron Yields from Spallation Reactions written by Chalk River Nuclear Laboratories. Neutron and Solid State Physics Branch and published by Chalk River, Ont. : Neutron and Solid State Physics Branch, Chalk River Laboratories. This book was released on 1992 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Double Differential Neutron Yields Produced by Proton Helium and Iron Interactions in Thick Aluminum Targets written by Natalie Ann McGirl and published by . This book was released on 2017 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent calculations of galactic cosmic ray (GCR) transport in enclosed, shielded space environments indicate that a minimum dose equivalent is achieved with aluminum shielding thicknesses near 20 g/cm2 [grams per centimeter squared]. Increases in the absorbed dose and dose equivalent with shielding thicknesses above 20 g/cm2 are believed to be caused by the production of light ions and neutrons in the thick shielding. However, uncertainties surround these calculations due to limited cross section and yield data for high-energy projectiles incident on thick targets. Thick-target neutron yields are particularly valuable measurements since they are produced over a wide range of energies by primary and secondary particles and include neutrons modified by transport through a material. Thus, a database of thick-target neutron yield measurements will help validate transport code calculations and quantify uncertainties between experimental and simulated data. In March 2016, secondary neutron yields from GCR-like projectiles impinging upon thick targets were measured at Brookhaven National Laboratory's NASA Space Radiation Laboratory. 400 and 800 AMeV [megaelectron volt per nucleon] iron and proton, and 400 AMeV helium projectiles were set incident upon 20, 40, and 60 g/cm2-thick aluminum targets, and a second 60 g/cm2 aluminum target was centered downstream to study backscattered neutrons at a later date. Upstream target neutron yields were measured with liquid scintillators at 10° [degrees], 30°, 45°, 60°, 80°, and 135° off the beam axis using the time-of-flight technique. Measurements were converted to double differential thick-target yields and compared with PHITS and MCNP transport model calculations. Comparisons with PHITS and MCNP revealed inconsistencies at low to intermediate energies, in addition to overestimations of the experimental yields at the 10° high-energy peak. Wide-angle yields at the shoulder energies were fairly well modeled for most systems, and yields at 135° were underestimated for the 400 AMeV projectile beams. Overall, both codes would benefit from improvements in their neutron production models, particularly below the peak or shoulder energies. This systematic study on secondary neutrons produced by thick-target interactions will be incorporated by NASA into a rigorous uncertainty quantification procedure, which will ultimately help determine optimal shielding thicknesses for future space applications.
Download or read book Thick target Neutron And Gamma ray Yields Induced by Medium energy Proton and Deuteron Bombardments written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Stopping samples of Lucite, Al, Fe, and 238U (Fe, and 238U) were irradiated with 330 MeV deuterons (260 MeV protons). For each target, neutron energy spectra and prompt .gamma.-ray yields were measured using the time-of-flight technique. The detector was a right cylindrical volume of deuterated benzene, 12.5-cm diameter x 7.5-cm long, located at 110° to the incident beam direction. The neutron yield and the prompt .gamma.-ray yield were found to depend upon the atomic number of the target and upon the incident projectile. The measured shape of the neutron energy spectrum was not strongly dependent on either the incident projectile or the target atomic number. A lower limit for absolute neutron yields was also obtained.
Download or read book Neutron Production by Proton Bombardment Below the p n Threshold written by Burridge Jennings and published by . This book was released on 1950 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutron Thresholds and Yields from Proton and Alpha Bombardment of Carbon 14 written by Richard Mark Sanders and published by . This book was released on 1956 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thick Target Neutron Yields from Spallation Reactions written by Chalk River Nuclear Laboratories and published by . This book was released on 1992 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: For very high power accelerator-based transmutation systems, thermodynamic considerations dictate targets of 50-100 cm diameter and 125-250 cm length. The spallation neturon yields calculated for these larger size targets are about 50-55 neturons per proton of energy 1.6 GeV, which would appear to be counter to the experimental value of 35 neutrons per proton extrapolated from the Cosmotron data, or even the theoretical value of 40 n/p for the 20 cm diameter target used in the experiments. This paper examines the two possible causes for this discrepancy: proton beam leakage from Cosmotron targets or neutron multiplication.
Download or read book The Absolute Yield of Low energy Neutrons from 190 Mev Proton Bombardment of Au Ag Ni Al and C written by Edward Gross and published by . This book was released on 1956 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Calculated Proton induced Thick target Neutron and Radionuclide Yields for E sub P D 100 MeV written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Earlier proton-induced thick-target yield calculations have been extended in proton energy range and to additional target elements, using the proton stopping cross section data of Anderson and Ziegler and cross sections modeled with the GNASH code. The targets now described include Be, C, O, Ne, Al, Si, Fe, Co, Ni, Cu, W, Pb and Bi. Thick-target yields are presented for these thirteen targets, with most extending to 100 MeV. 13 refs., 3 figs., 13 tabs.
Download or read book The Neutron Yield from Thick Lithium Targets at Proton Energies from 3 to 10 MeV written by and published by . This book was released on 1969 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectrum and Yield of Neutrons from 31 5 Mev Proton Bombardment of Selected Isotopes of Cobalt and Nickel written by Hoyt Alan Bostick and published by . This book was released on 1959 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
