Surface Conversion Techniques for Low Energy Neutral Atom Imagers - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Surface Conversion Techniques for Low Energy Neutral Atom Imagers write by National Aeronautics and Space Administration (NASA). This book was released on 2018-07-12. Surface Conversion Techniques for Low Energy Neutral Atom Imagers available in PDF, EPUB and Kindle. This investigation has focused on development of key technology elements for low energy neutral atom imaging. More specifically, we have investigated the conversion of low energy neutral atoms to negatively charged ions upon reflection from specially prepared surfaces. This 'surface conversion' technique appears to offer a unique capability of detecting, and thus imaging, neutral atoms at energies of 0.01 - 1 keV with high enough efficiencies to make practical its application to low energy neutral atom imaging in space. Such imaging offers the opportunity to obtain the first instantaneous global maps of macroscopic plasma features and their temporal variation. Through previous in situ plasma measurements, we have a statistical picture of large scale morphology and local measurements of dynamic processes. However, with in situ techniques it is impossible to characterize or understand many of the global plasma transport and energization processes. A series of global plasma images would greatly advance our understanding of these processes and would provide the context for interpreting previous and future in situ measurements. Fast neutral atoms, created from ions that are neutralized in collisions with exospheric neutrals, offer the means for remotely imaging plasma populations. Energy and mass analysis of these neutrals provides critical information about the source plasma distribution. The flux of neutral atoms available for imaging depends upon a convolution of the ambient plasma distribution with the charge exchange cross section for the background neutral population. Some of the highest signals are at relatively low energies (well below 1 keV). This energy range also includes some of the most important plasma populations to be imaged, for example the base of the cleft ion fountain. Quinn, J. M. Unspecified Center NAS8-39950...
Scientific and Technical Aerospace Reports
Scientific and Technical Aerospace Reports - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Scientific and Technical Aerospace Reports write by . This book was released on 1995. Scientific and Technical Aerospace Reports available in PDF, EPUB and Kindle. 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.
Advances in Low Energy Neutral Atom Imaging Techniques
Advances in Low Energy Neutral Atom Imaging Techniques - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Advances in Low Energy Neutral Atom Imaging Techniques write by . This book was released on 1993. Advances in Low Energy Neutral Atom Imaging Techniques available in PDF, EPUB and Kindle. Recently proposed low energy neutral atom (LENA) imaging techniques use a collisional process to convert the low energy neutrals into ions before detection. At low energies, collisional processes limit the angular resolution and conversion efficiencies of these devices. However, if the intense ultraviolet light background can be suppressed, direct LENA detection is possible. We present results from a series of experiments designed to develop a novel filtering structure based on free-standing transmission gratings. If the grating period is sufficiently small, free standing transmission gratings can be employed to substantially polarize ultraviolet (UV) light in the wavelength range 300 Å to 1500 Å. If a second grating is placed behind the first grating with its axis of polarization oriented at a right angle to the first's, a substantial attenuation of UV radiation is achievable. ne neutrals will pass through the remaining open area of two gratings and be detected without UV background complications. We have obtained nominal 2000 Å period (1000 Å bars with 1000 Å slits) free standing, gold transmission gratings and measured their UV and atomic transmission characteristics. The geometric factor of a LENA imager based on this technology is comparable to that of other proposed LENA imagers. In addition, this of imager does not distort the neutral trajectories, allowing for high angular resolution.
Measurement Techniques in Space Plasmas
Measurement Techniques in Space Plasmas - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Measurement Techniques in Space Plasmas write by Robert F. Pfaff. This book was released on 1998-02-04. Measurement Techniques in Space Plasmas available in PDF, EPUB and Kindle. Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 103. Space plasma measurements are conducted in a hostile, remote environment. The art and science of measurements gathered in space depend therefore on unique instrument designs and fabrication methods to an extent perhaps unprecedented in experimental physics. In-situ measurement of space plasmas constitutes an expensive, unforgiving, and highly visible form of scientific endeavor.
Neutral-atom Astronomy: Plasma Diagnostics From The Aurora To The Interstellar Medium
Neutral-atom Astronomy: Plasma Diagnostics From The Aurora To The Interstellar Medium - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Neutral-atom Astronomy: Plasma Diagnostics From The Aurora To The Interstellar Medium write by Ke Chiang Hsieh. This book was released on 2022-05-20. Neutral-atom Astronomy: Plasma Diagnostics From The Aurora To The Interstellar Medium available in PDF, EPUB and Kindle. Astronomy has been associated with the detection of electromagnetic waves or photons from within and beyond the solar system, ranging from Radio to Gamma-ray Astronomy. Particle Astrophysics, including Neutrino and Dark-Matter Astrophysics today, started with the discovery of cosmic rays in 1911. The Space Age expanded particle observations to in-situ studies of lower energy electrons and ions with a variety of charge states in space plasmas traversed by spacecraft. Remote observation of space plasmas became possible only after the discovery of energetic neutral atoms (ENAs) in space in 1950.This book is a primer for those who wish to learn more about the origins of ENAs, related detection techniques, and how ENA images and spectra can be used to study space plasmas beyond the reach of spacecraft. It tells a comprehensive story from the first encounters with ENAs in the Earth's magnetosphere to Neutral-Atom Astronomy of the edge of the heliosphere and the interstellar medium. This story includes how ion mass spectrographs evolved into ENA imagers, overcoming the technical challenges, how to extract information from ENA data, and a variety of diagnostic applications on the magnetosphere, interplanetary space, other solar-system objects, the heliospheric boundary, the local interstellar medium, and a glimpse into the future of Neutral-Atom Astronomy.The authors hope to inform and inspire readers to further enrich this field of study.
