Download or read book Gamma ray Production Cross Sections in Multiple Channels for Neutron Induced Reaction on 48Ti for En written by and published by . This book was released on 2006 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Prompt [gamma]-ray production cross sections were measured on a 48Ti sample for incident neutron energies from 1 MeV to 200 MeV. Partial [gamma]-ray cross sections for transitions in 45−48Ti, 45−48Sc, and 43−45Ca were determined. The observation of about 130 transitions from 11 different isotopes in the present work provides a demanding test of reaction model calculations, and is the first study in this mass region to extract partial [gamma]-ray cross sections for many different reaction channels over a wide range of incident neutron energies. The neutrons were produced by the Los Alamos National Laboratory spallation neutron source located at the LANSCE/WNR facility. The prompt-reaction [gamma] rays were detected with the large-scale Compton-suppressed GErmanium Array for Neutron Induced Excitations (GEANIE). Event neutron energies were determined by the time-of-flight technique. The [gamma]-ray excitation functions were converted to partial [gamma]-ray cross sections and then compared with model calculations using the enhanced GNASH reaction code. Compound nuclear, pre-equilibrium emission and direct reaction mechanisms are included. Overall the model calculations of the partial [gamma]-ray cross sections are in good agreement with measured values.

Download or read book 48Ti n Xnpa gamma Reaction Cross Sections Using Spallation Neutrons for E sub N written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: [Gamma]-ray excitation functions have been measured for the interaction of fast neutrons with 48Ti (neutron energy from 1 MeV to 250 MeV). The Los Alamos National Laboratory spallation neutron source, at the LANSCE/WNR facility, provided a ''white'' neutron beam which is produced by bombarding a natural W target with a pulsed proton beam. The prompt-reaction [gamma] rays were measured with the large-scale Compton-suppressed Ge spectrometer, GEANIE. Neutron energies were determined by the time-of-flight technique. Excitation functions were converted to partial [gamma]-ray cross sections, taking into account the dead-time correction, the target thickness, the detector efficiency, and neutron flux (monitored with an in-line fission chamber). The data analysis is presented here for neutron energies between 1 to 20 MeV. Partial [gamma]-ray cross sections for transitions in {sup 47,48}Ti, 48Sc, and 45Ca have been determined. These results are compared to Hauser-Feshbach predictions calculated using the STAPRE code, which includes compound nuclear and pre-equilibrium emission. The partial cross sections for [gamma] rays, whose discrete [gamma]-ray cascade path leads to the ground state in 48Ti, 47Ti, 48Sc, and 45Ca have been summed to obtain estimates of the lower limits for reaction cross sections. Partial cross sections for unobserved [gamma]-rays are predicted from the STAPRE code. These lower limits are combined with Hauser-Feshbach calculations to deduce 48Ti(n, n')48Ti, 48Ti(n,2n)47Ti, 48Ti(n, p)48Sc, and 48Ti(n, [alpha])45Ca reaction channel cross sections.

Download or read book Cross Section Standards for Neutron induced Gamma ray Production in the MeV Energy Range written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gamma-ray cross section standards for neutron-induced reactions are important in enabling the accurate determination of absolute cross sections from relative measurements of gamma-ray production. In our work we observed a need for improvement in these standards. In particular there are large discrepancies between evaluations of the {sup nat}Fe(n, n1'[gamma]) cross section for the 847-keV gamma ray. We have performed (1) absolute cross section measurements, (2) measurements relative to the {sup nat}Cr(n, n1'[gamma]) 1434-keV gamma ray, and (3) comparisons using measured total and elastic scattering cross sections to refine our knowledge of the Fe cross section and the closely linked inelastic channel cross section for Fe. Calculation of integral tests of the cross section libraries may indicate that adjustment of the angular distributions of the neutron elastic and inelastic scattering may be needed.

Download or read book More 14 MeV Neutron induced Gamma ray Production Cross Sections written by and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of Gamma ray Production Cross Sections in Neutron induced Reactions for Al and Pb written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sup 48 Ti n Xnpa Gamma Reaction Cross Sections Using Spallation Neutrons for E Sub N written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: [Gamma]-ray excitation functions have been measured for the interaction of fast neutrons with [sup 48]Ti (neutron energy from 1 MeV to 250 MeV). The Los Alamos National Laboratory spallation neutron source, at the LANSCE/WNR facility, provided a ''white'' neutron beam which is produced by bombarding a natural W target with a pulsed proton beam. The prompt-reaction [gamma] rays were measured with the large-scale Compton-suppressed Ge spectrometer, GEANIE. Neutron energies were determined by the time-of-flight technique. Excitation functions were converted to partial [gamma]-ray cross sections, taking into account the dead-time correction, the target thickness, the detector efficiency, and neutron flux (monitored with an in-line fission chamber). The data analysis is presented here for neutron energies between 1 to 20 MeV. Partial [gamma]-ray cross sections for transitions in [sup 47,48]Ti, [sup 48]Sc, and [sup 45]Ca have been determined. These results are compared to Hauser-Feshbach predictions calculated using the STAPRE code, which includes compound nuclear and pre-equilibrium emission. The partial cross sections for [gamma] rays, whose discrete [gamma]-ray cascade path leads to the ground state in [sup 48]Ti, [sup 47]Ti, [sup 48]Sc, and [sup 45]Ca have been summed to obtain estimates of the lower limits for reaction cross sections. Partial cross sections for unobserved [gamma]-rays are predicted from the STAPRE code. These lower limits are combined with Hauser-Feshbach calculations to deduce [sup 48]Ti(n, n')[sup 48]Ti, [sup 48]Ti(n,2n)[sup 47]Ti, [sup 48]Ti(n, p)[sup 48]Sc, and [sup 48]Ti(n, [alpha])[sup 45]Ca reaction channel cross sections.

Download or read book Reports to the AEC Nuclear Cross Sections Advisory Group written by A. B. Smith and published by . This book was released on 1965 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of 235U Neutron Cross Section and Gamma Ray Production for ENDF B V written by M. R. Bhat and published by . This book was released on 1980 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High resolution Neutron induced gamma ray Production Cross Sections for Oxygen and Beryllium for Neutron Energies from 4 to 200 MeV written by and published by . This book was released on 2001 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of discrete gamma-ray spectra from neutron-induced reactions on a Be0 sample have been performed using the broad-spectrum neutron spallation source of the WNR facility at LANSCE. Incident neutron energies were determined by the time-of-flight technique. Two high-purity Ge detectors were used to detect gamma rays in the energy range from 0.150 to 9.0 MeV. Spectra were measured at seven angles. Absolute gamma-ray production cross sections were delermined from the measured neutron fluence and detector efficiencies. A new evaluation of the reaction cross sections has been performed based on this data. GNASH model calculations were performed for 20

Download or read book Reports to the AEC Nuclear Cross Sections Advisory Group written by and published by . This book was released on 1958-11 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Conference on Neutron Cross Section Technology written by P. B. Hemmig and published by . This book was released on 1966 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Gamma ray Production Cross Sections from Neutron induced Reactions on Tungsten written by and published by . This book was released on 1974 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Gamma Ray Production Cross Sections written by and published by . This book was released on 1964 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Gamma production cross sections are presented as a function of l6 neutron lethargy groups and 11 photon energy groups for 13 elements and isotopes. They were computed by the program GAMMA-P and account for the production of gamma rays by neutron radiative capture, neutron inelastic scattering, neutron induced fissioning, and (n, alpha) reactions. (auth).

Download or read book Gamma ray Production Cross Sections from Neutron Interactions with Iron written by and published by . This book was released on 2002 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: The initial purpose of this experiment was to provide a consistent data base of neutron-induced gamma-ray production cross sections over a large energy range for use in estimating elemental composition of the martian surface by observing gamma rays produced by cosmic ray interactions on the planet's surface [Bo02]. However, these data should be useful for other projects such as oil-well logging, accelerator transmutation of nuclear waste, shielding calculations, gamma-ray heating for nuclear reactors and verification of nuclear model calculations and databases. The goal of the measurements was to collect data on the strongest gamma rays from many samples of interest. Because of the available beam time this meant that many of the measurcments were rather short. Despite the short running time the large samples used and the good beam intensity resulted in very satisfactory results. The samples, chosen mainly as common constituents of rock and soil and measured in the same few week period, include: B &, BN, C, Al, Mg, Si, S, Cay Ti, Cr, Mn, and Fe. Be was also used as a neutron scatterer that only produces one gamma ray (478 keV from 7Li) with appreciable intensity. Thus Be can serve as a measure of neutron-induced backgrounds. In this first paper we present results for Fe.

Download or read book Neutron Cross Sections and Technology written by David T. Goldman and published by . This book was released on 1968 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Inelastic Cross Sections from Gamma ray Measurements written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of gamma rays following neutron induced reactions have been studied with the Germanium Array for Neutron-induced Excitations (GEANIE) at the Los Alamos Neutron Science Center (LANSCE) for many years. Gamma-ray excitation functions and coincidence studies provide insight into nuclear reaction mechanisms as well as expanding our knowledge of energy levels and gamma-rays. Samples studied with Ge detectors at LANSCE range from Be to Pu. Fe, Cr and Ti have been considered for use as reference cross sections. An overview of the measurements and efforts to create a reliable neutron-induced gamma-ray reference cross section will be presented.

Download or read book Neutron Induced Inelastic Cross Sections of 150Sm for En written by R. O. Nelson and published by . This book was released on 2006 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cross-section measurements were made of prompt gamma-ray production as a function of incident neutron energy (E{sub n} = 1 to 35 MeV) on an enriched (95.6%) {sup 150}Sm sample. Energetic neutrons were delivered by the Los Alamos National Laboratory spallation neutron source located at the Los Alamos Neutron Science Center (LANSCE) facility. The prompt-reaction gamma rays were detected with the large-scale Compton-suppressed Germanium Array for Neutron Induced Excitations (GEANIE). Neutron energies were determined by the time-of-flight technique. The {gamma}-ray excitation functions were converted to partial {gamma}-ray cross sections taking into account the dead-time correction, target thickness, detector efficiency and neutron flux (monitored with an in-line fission chamber). Partial {gamma}-ray cross sections were predicted using the Hauser-Feshbach statistical reaction code GNASH. Above E{sub n} {approx} 8 MeV the pre-equilibrium reaction process dominates the inelastic reaction. The spin distribution transferred in pre-equilibrium neutron-induced reactions was calculated using the quantum mechanical theory of Feshbach, Kerman, and Koonin (FKK). These pre-equilibrium spin distributions were incorporated into a new version of GNASH and the {gamma}-ray production cross sections were calculated and compared with experimental data. The difference in the partial {gamma}-ray cross sections using spin distributions with and without pre-equilibrium effects is discussed.