Download or read book Thermal Design and Performance of the Gamma Ray Spectrometer for the MESSENGER Spacecraft written by W. Miller and published by . This book was released on 2004 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: A gamma-ray spectrometer (GRS) has been built and delivered to the Mercury MESSENGER spacecraft which launched on August 3, 2004, from Cape Canaveral, Florida. The GRS, a part of seven scientific instruments on board MESSENGER, is based on a coaxial high-purity germanium detector. Gamma-ray detectors based on germanium have the advantage of providing excellent energy resolution, which is critical to achieving the science goals of the mission. However, germanium has the disadvantage that it must operate at cryogenic temperatures (typically {approx}80 K). This requirement is easy to satisfy in the laboratory but difficult near Mercury, which has an extremely hot thermal radiation environment. To cool the detector, a Stirling cycle mechanical cooler is employed. In addition, radiation and conduction techniques a are used to reduce the GRS heat load. Before delivering the flight sensor, a complete thermal prototype was built and tested. The results of these test, including thermal design, radiative and conductive heat loads, and cooler performance are described.
Download or read book Treatise on Geophysics written by and published by Elsevier. This book was released on 2015-04-17 with total page 5604 pages. Available in PDF, EPUB and Kindle. Book excerpt: Treatise on Geophysics, Second Edition, is a comprehensive and in-depth study of the physics of the Earth beyond what any geophysics text has provided previously. Thoroughly revised and updated, it provides fundamental and state-of-the-art discussion of all aspects of geophysics. A highlight of the second edition is a new volume on Near Surface Geophysics that discusses the role of geophysics in the exploitation and conservation of natural resources and the assessment of degradation of natural systems by pollution. Additional features include new material in the Planets and Moon, Mantle Dynamics, Core Dynamics, Crustal and Lithosphere Dynamics, Evolution of the Earth, and Geodesy volumes. New material is also presented on the uses of Earth gravity measurements. This title is essential for professionals, researchers, professors, and advanced undergraduate and graduate students in the fields of Geophysics and Earth system science. Comprehensive and detailed coverage of all aspects of geophysics Fundamental and state-of-the-art discussions of all research topics Integration of topics into a coherent whole
Download or read book Semiconductor Radiation Detectors written by Alan Owens and published by CRC Press. This book was released on 2019-05-31 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: Choice Recommended Title, July 2020 Bringing together material scattered across many disciplines, Semiconductor Radiation Detectors provides readers with a consolidated source of information on the properties of a wide range of semiconductors; their growth, characterization and the fabrication of radiation sensors with emphasis on the X- and gamma-ray regimes. It explores the promise and limitations of both the traditional and new generation of semiconductors and discusses where the future in semiconductor development and radiation detection may lie. The purpose of this book is two-fold; firstly to serve as a text book for those new to the field of semiconductors and radiation detection and measurement, and secondly as a reference book for established researchers working in related disciplines within physics and engineering. Features: The only comprehensive book covering this topic Fully up-to-date with new developments in the field Provides a wide-ranging source of further reference material
Download or read book GeMini written by and published by . This book was released on 2008 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The next-generation mechanically-cooled germanium spectrometer has been developed. GeMini (MINIature GErmanium spectrometer) has been designed to bring high-resolution gamma-ray spectroscopy to a range of demanding field environments. Intended applications include short-notice inspections, border patrol, port monitoring and emergency response, where positive nuclide identification of radioactive materials is required but power and liquid cryogen are not easily available. GeMini weighs 2.75 kg for the basic instrument and 4.5 kg for the full instrument including user interface and ruggedized hermetic packaging. It is very low power allowing it to operate for 10 hours on a single set of rechargeable batteries. This instrument employs technology adapted from the gamma-ray spectrometer currently flying on NASA's Mercury MESSENGER spacecraft. Specifically, infrared shielding techniques allow for a vast reduction of thermal load. This in turn allows for a smaller, lighter-weight design, well-suited for a hand-held instrument. Three working prototypes have been built and tested in the lab. The measured energy resolution is 3 keV fwhm at 662 keV gamma-rays. This paper will focus on the design and performance of the instrument.
Download or read book The MESSENGER Mission to Mercury written by D.L. Domingue and published by Springer Science & Business Media. This book was released on 2007-12-19 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first book to present the science and instruments of NASA’S MESSENGER space mission. The articles, written by the experts in each area of the MESSENGER mission, describe the mission, spacecraft, scientific objectives, and payload. The book is of interest to all potential users of the data returned by the mission, to those studying the nature of Mercury, and by all those interested in the design and implementation of planetary exploration missions.
Download or read book Mercury written by Sean C. Solomon and published by Cambridge University Press. This book was released on 2018-12-20 with total page 601 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offers an authoritative synthesis of knowledge of the planet Mercury after the MESSENGER mission, for researchers and students in planetary science.
Download or read book 2004 IEEE Nuclear Science Symposium Conference Record written by and published by . This book was released on 2004 with total page 772 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of X ray and Gamma ray Astrophysics written by Cosimo Bambi and published by Springer Nature. This book was released on with total page 5912 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Design and Performance of a Portable Gamma ray Spectrometer written by Wayne Lunt and published by . This book was released on 1972 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Conference Record written by and published by . This book was released on 2004 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1976 with total page 1004 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Design of a Multi Channel Ultra High Resolution Superconducting Gamma Ray Spectrometer written by M. F. Cunningham and published by . This book was released on 2004 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superconducting Gamma-ray microcalorimeters operated at temperatures around {approx}0.1 K offer an order of magnitude improvement in energy resolution over conventional high-purity Germanium spectrometers. The calorimeters consist of a {approx}1 mm{sup 3} superconducting or insulating absorber and a sensitive thermistor, which are weakly coupled to a cold bath. Gamma-ray capture increases the absorber temperature in proportion to the Gamma-ray energy, this is measured by the thermistor, and both subsequently cool back down to the base temperature through the weak link. We are developing ultra-high-resolution Gamma-ray spectrometers based on Sn absorbers and superconducting Mo/Cu multilayer thermistors for nuclear non-proliferation applications. They have achieved an energy resolution between 60 and 90 eV for Gamma-rays up to 100 keV. We also build two-stage adiabatic demagnetization refrigerators for user-friendly detector operation at 0.1 K. We present recent results on the performance of single pixel Gamma-ray spectrometers, and discuss the design of a large detector array for increased sensitivity.
Download or read book Thermal Design Evolution and Performance of the Surveyor Spacecraft written by J. M. F. Vickers and published by . This book was released on 1968 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Simulation of the Lunar Prospector s Gamma Ray Spectrometer written by Marie C. Grimmer and published by . This book was released on 1997 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: The expected response of the Lunar Prospector's Gamma Ray Spectrometer instrument was predicted using a Monte Carlo simulation. The full lunar spectrum was generated using 90 lines and a continuum gamma ray background taken from Apollo 15 and 16 data. The Monte Carlo program uses the exact dimensions and composition of the Gamma Ray Spectrometer in order to most accurately predict spectral performance, assuming an operating temperature on orbit of -30 degrees Celsius. The Gamma Ray Spectrometer will be launched aboard the Lunar Prospector spacecraft on October 24, 1997. The Lunar Prospector will assume a 100 km altitude orbit around the moon, allowing the Gamma Ray Spectrometer to map the elemental composition of the surface. The simulated Gamma Ray Spectrometer response can be used as a comparison for the actual data in order to determine how well the spectrometer is working.
Download or read book Scientific Considerations in the Design of the Mars Observer Gamma ray Spectrometer written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cosmic-ray primary and secondary particles induce characteristic gamma-ray and neutron emissions from condensed bodies in our solar system. These characteristic emissions can be used to obtain qualitative and quantitative elemental analyses of planetary surfaces from orbital altitudes. Remote sensing gamma-ray spectroscopy has been successfully used to obtain elemental composition of the Moon and Mars during United States Apollo 15 and 16 missions and the Soviet Luna and Mars missions. A remote sensing gamma-ray and neutron spectrometer will be included aboard the United States Mars Observer Mission. If proper care is not taken in the design of the spectrometer and choice of materials in the construction of the detector system and spacecraft, the sensitivity of these remote sensing spectrometers can be greatly degraded. A discussion of these design and material selection problems is presented. 16 refs., 5 figs., 3 tabs.
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.
Download or read book Designing and Testing the High purity Germanium Gamma ray Spectrometer for the Dragonfly Mission to Titan written by Nathan Robert Hines and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Dragonfly Mission will send a high-purity germanium gamma-ray spectrometer one billion miles from Earth to investigate the composition of the icy world Titan, Saturn's largest moon. The detector will be mounted on an autonomous rotorcraft and will travel over 100 miles across Titan's 94 K surface. A deuterium-tritium neutron generator will interrogate Titan's surface, producing gamma rays through neutron capture and inelastic scatter interactions. The gamma-ray spectrometer will measure these gamma-rays to determine the elemental composition of Titan's surface. The spectrometer was designed to operate in this unique environment, and was subjected to multiple tests to ensure design viability. The system was shown to be operable after being subjected to rocket-launch like vibration loads. A model was developed to simulate detector thermal performance and was shown to be accurate by comparison to experimental data. The model predicts that the detector will passively cool to an operating temperature of 100 K within seven days of the detector arriving on Titan's surface, meeting mission requirements. The ability to anneal, or heat, the germanium crystal to repair radiation damage under Titan-like thermal conditions was demonstrated. Annealing the detector for a low input power requires that vacuum be maintained inside the cryostat. Vacuum performance was thoroughly characterized, and long-duration vacuum maintenance was demonstrated using a non-evaporable getter. Additionally, sensitivity to neutron-induced gamma rays was demonstrated under Titan-like conditions. A radiation damage study was performed to investigate 1) the effects of neutron damage on germanium energy resolution and 2) the anneal time required to repair neutron damage. A correlation between neutron fluence and spectrometer energy resolution is presented and an anneal recipe is provided.
