Download or read book Measurements of Cross Sections Relevant To Gamma ray Line Astronomy written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Gamma-ray production cross sections have been measured for the .gamma.-ray lines which are mostly strongly excited in the proton bombardment of C, O, Mg, Si, and Fe targets of natural isotopic composition. High resolution germanium detectors were used to collect .gamma.-ray spectra at proton bombarding energies of 20, 30, 33, 40 and 50 MeV. 6 refs., 6 figs.
Download or read book Gamma ray Astrophysics written by Carl E. Fichtel and published by . This book was released on 1997 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gamma Ray Astronomy written by E.L. Chupp and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Observation of discrete energy electromagnetic emissions from celestial objects in the radio, IR, optical, lN, and X-ray spectral regions has dramatically advanced our know ledge in the field of astrophysics. It is expected that identification of nuclear 'Y-ray line emissions from any cosmic source would also prove to be a powerful new tool for probing the Universe. Since the publication of Morrison's work in 1958, many experiments were carried out searching for evidence of 'Y-ray lines from cosmic sources, however with little success. Only a few positive experimental results have been reported, in spite of an expenditure of considerable effort by many people: in particular, the possible Galactic Center emission line (473 to 530keV) and 'Y-ray lines at several energies (e. g. , 0. 5 MeV and 2. 2 MeV) associated with large solar flares. Both of these observations are unconfirmed by indepen dent observations (ca. 1975). The high energy 'Y-rays (>30MeV) from the Galactic Center are at least partly due to the decay of 1[0 mesons, which are of unique energy (67. 5 MeV) in the 1[0 rest frame only. The reasons for the limited amount of data avail able in this field, even though early theoretical predictions were very optimistic regarding fluxes of nuclear lines, are that experimental efforts are plagued with high backgrounds and low fluxes, and that development of instruments with telescopic properties in the energy range of interest is difficult.
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 NASA Technical Memorandum written by and published by . This book was released on 1984 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Hubble Deep Field written by Space Telescope Science Institute (U.S.). Symposium and published by Cambridge University Press. This book was released on 1998-10-13 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hubble Deep Field (HDF) is the deepest optical image of the Universe ever obtained. It is the result of a 150-orbit observing programme with the Hubble Space Telescope. It provides a unique resource for researchers studying the formation and evolution of stars and galaxies. This timely volume provides the first comprehensive overview of the HDF and its scientific impact on our understanding in cosmology. It presents articles by a host of world experts who gathered together at an international conference at the Space Telescope Science Institute. The contributions combine observations of the HDF at a variety of wavelengths with the latest theoretical progress in our understanding of the cosmic history of star and galaxy formation. The HDF is set to revolutionize our understanding in cosmology. This book therefore provides an indispensable reference for all graduate students and researchers in observational or theoretical cosmology.
Download or read book Measurement of Gamma ray Total Absorption Cross Sections Using a sup 56 Co Source written by and published by . This book was released on 2008 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have used a 150 MBq [sup 56]Co source to perform gamma-ray total absorption cross section measurements with very high precision. The use of [sup 56]Co allowed us to simultaneously measure the total cross section at 15 energies ranging from 0.847 MeV to 3.451 MeV. Seven sample materials were measured: Be, C, Cu, Ta, W, Pb, and U. In general, the measurement precision is better than 0.5% and in all cases better than 1.3%.
Download or read book Genesis and Propagation of Cosmic Rays written by M.M. Shapiro and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Study Institute, Erice, Sicily, Italy, June 1-9, 1986
Download or read book Cross Sections for Production of the 15 10 MeV and Other Astrophysically Significant Gamma ray Lines Through Excitation and Spallation of 12C and 16O with Protons written by and published by . This book was released on 1986 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Very High Energy Cosmic Gamma Radiation written by Felix A. Aharonian and published by World Scientific. This book was released on 2004 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gamma ray astronomy, the branch of high energy astrophysics that studies the sky in energetic ?-ray photons, is destined to play a crucial role in the exploration of nonthermal phenomena in the Universe in their most extreme and violent forms. The great potential of this discipline offers impressive coverage of many OC hot topicsOCO of modern astrophysics and cosmology, such as the origin of galactic and extragalactic cosmic rays, particle acceleration and radiation processes under extreme astrophysical conditions, and the search for dark matter."
Download or read book Measurement of 238U n N gamma and 7Li n N gamma Gamma ray Production Cross Sections written by G. L. Morgan and published by . This book was released on 1979 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book In beam Measurements of Inclusive Differential Cross Sections for the Production of Gamma Radiation from 30 67 5 MeV Protons on Thin Targets of Aluminum Iron Titanium and Uranium written by Guy Alton Letteer and published by . This book was released on 1988 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cross Sections for Production of the 15 10 MeV and Other Astrophysically Significant Gamma ray Lines Through Excitation and Spallation of Sup 12 C and Sup 16 O with Protons written by and published by . This book was released on 1986 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1988 Part 1 written by U. Esser and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1266 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: "Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundamental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ...The abstracts are classified under more than a hundred subject categories, thus permitting a quick survey of the whole extended material. The AAA is a valuable and important publication for all students and scientists working in the fields of astronomy and related sciences. As such it represents a necessary ingredient of any astronomical library all over the world." Space Science Reviews#1 "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine#2
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 Remote Compositional Analysis written by Janice L. Bishop and published by Cambridge University Press. This book was released on 2019-11-28 with total page 655 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive overview of the spectroscopic, mineralogical, and geochemical techniques used in planetary remote sensing.
