Radio-star scintillations and spread F in the auroral zone.
Radio star Cassiopeia A scintillations and spread-F in auroral zone
AURORAL ZONE↗
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Results for “Scintillation”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The scale size of scintillation-producing irregularities in the auroral ionosphere.
F layer irregularities transverse scale measurements by two-frequency scintillation-ratio technique yielding 600-700 m scales in auroral zone
SCINTILLATION SPECTROMETER↗
Scintillation effects on radio wave propagation through solar corona
When RF waves pass through the solar corona and solar wind regions close to the Sun, strong scintillation effects appear at their amplitude, frequency and phase, especially in the regions very close to the Sun (less than 4 solar radius).
solar corona solar wind propagation scintillation ↗
Radiowave Phase Scintillation and Precision Doppler Tracking of Spacecraft
Phase scintillation cause by propagation through irregularities in the solar wind, ionosphere, and tropospher, introduces noise in spacecraft radio science experiments. The observations reported here are uses to refine the propagation noise model for Doppler tracking of deep space probes.
Phase Scintillation Precision Doppler↗
Doppler Scintillation Measurements of Coronal Streamers Embedded in the Heliospheric Current Sheet Close to the Sun
Doppler scintillation transients overlying the neutral line and lasting a fraction of a day (solar source of several degrees)are the apparent interplanetary manifestation of coronal streamers embedded in the heliospheric current sheet.
doppler scintillation doppler coronal streamers he↗
A Summary of - An Earth-to-Deep Space Communications System with Adaptive Tilt and Scintillation Correction Using Near-Earth Relay Mirrors
Optical telecommunication will be the next technology for wide-band Earth/space communication. Uncompensated propagation through the Earth's atmosphere (e.g., scintillation and wavefront tilt) fundamentally degrade communication to distant spcaecraft.
Optics↗
The Scintillation Prediction Observations Research Task (SPORT) Mission
SPORT is a science mission using a 6U CubeSat and integrated ground network that will (1) advance understanding and (2) enable improved predictions of scintillation occurrence that impact GPS signals and radio communications. This is the science of Space Weather. SPORT is an international partnership with NASA, U.S. institutions, the Brazilian National Institute for Space Research (INPE), and the Technical Aeronautics Institute under the Brazilian Air Force Command Department (DCTA/ITA).
SPORT↗
The Scintillation Prediction Observations Research Task (SPORT): an International Science Mission Using a Cubesat
The Scintillation Prediction Observations Research Task (SPORT) is a 6U CubeSat mission to address the compelling but difficult problem of understanding the preconditions leading to equatorial plasma bubbles. The scientific literature describes the preconditions in both the plasma drifts and the density profiles related to bubble formations that occur several hours later in the evening. Most of the scientific discovery has resulted from observations at a single site, within a single longitude sector, from Jicamarca, Peru. SPORT will provide a systematic study of the state of the pre-bubble conditions at all longitudes sectors to enhance understanding between geography and magnetic geometry. SPORT is an international partnership between National Aeronautics and Space Administration (NASA), the Brazilian National Institute for Space Research (INPE), and the Technical Aeronautics Institute under the Brazilian Air Force Command Department (DCTA/ITA), and encouraged by U.S. Southern Command. This talk will present an overview of the SPORT mission, observation strategy, and science objectives to improve predictions of ionospheric disturbances that affect radio propagation of telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator.
Scintillation Prediction Observations↗
Mass Flux in the Ecliptic Plane and Near the Sun Deduced from Doppler Scintillation
In this paper, we use Doppler scintillation measurements to investigate mass flux of these two types of solar wind inside 0.3AU, where in-situ measurements have not been possible.
solar↗
Solar Cycle Variation of Interplanetary Disturbances Observed as Doppler Scintillation Transients
Interplanetary disturbances characterized by plasma that is more turbulent and/or moves faster than the background solar wind are readily detected as transients in Doppler scintillation measurements of the near-Sun solar wind.
Doppler↗
Comparison of BCF-10, BCF-12, and BCF-20 Scintillating Fibers for Use in a 1-Dimensional Linear Sensor
One-dimensional fiber-bundle arrays may prove useful in a number of radiation sensing applications where radiation detection over large areas is needed. Tests have been performed to evaluate the light generation and transmission characteristics of 15-meter long, 10-fiber bundles of BCF-10, BCF-12, and BCF-20 scintillating fibers (Saint Gobain) exposed to collimated gamma-ray sources. The test set-up used one R9800 (Hamamatsu) photomultiplier tube (PMT) at each end, with a high-speed waveform digitizer to collect data. Time constraints were imposed on the waveform data to perform time-of-flight analysis of the events in the fiber bundles, eliminating spurious noise pulses in the high gain PMTs and also allowing 1-dimensional localization of interactions along the lengths of the fiber bundles. This paper will present the results of these measurements including the attenuation coefficients of the two fiber types and the timing resolution (position uncertainty) possible for each fiber bundle when using the R9800 PMTs.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Counterintuitive MCNPX Results for Scintillator Surface Roughness Effect
We have reported on our recent MCNPX simulation results of energy deposition for a group of 8 scintillation detectors, coupled with various rough surface patterns. The MCNPX results generally favored the detectors with various rough surface patterns. The observed MCNPX results are not fully explained by this work.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Passive Measurement of Organic-Scintillator Neutron Signatures for Nuclear Safeguards Applications
At nuclear facilities, domestically and internationally, most measurement systems used for nuclear materials’ control and accountability rely on He-3 detectors. Due to resource shortages, alternatives to He-3 systems are needed. This paper presents preliminary simulation and experimental efforts to develop a fast-neutron-multiplicity counter based on liquid organic scintillators. This mission also provides the opportunity to broaden the capabilities of such safeguards measurement systems to improve current neutron-multiplicity techniques and expand the scope to encompass advanced nuclear fuels.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Thermal Variance Investigation and Scintillation Mechanisms of Cs 2 LiLaBr 6-x Cl x :Ce (CLLBC) and Cs 2 LiYBr 6 :Ce (CLYB)
We perform an investigation into the scintillation processes and performance of elpasolites Cs 2 LiLaBr 6-x Cl x :Ce (CLLBC) and Cs 2 LiYBr 6 :Ce (CLYB) using a thermal cycle over a range of -20 to +50º C. At 10º increments, we acquire data with both a waveform digitizer and charge-integrating electronics. We identify decay components and evaluate decay times, thermal neutron gamma-equivalent energy (GEE), and pulse shape discrimination (PSD) performance. Results are compared to common Cs 2 LiYCl 6 :Ce (CLYC).
36 MATERIALS SCIENCE↗
R&D100 Winner 2014: Triplet-Harvesting Plastic Scintillator
A new class of solid-state organic scintillators that enables efficient multi-mode detection of fast neutrons from Special Nuclear Materials such as Uranium-235 and Plutonium-239.
36 MATERIALS SCIENCE↗
Evaluation, Refurbishment, and Characterization of Fast Neutron Scintillators for the TREAT Fuel Motion Monitoring System
This paper details work being performed at the Idaho National Laboratory (INL) to evaluate, refurbish, and characterize proton-recoil scintillation (PRS) detectors utilized in a 360 channel array for the measurement of fast neutrons in a standalone system historically called a hodoscope located in the Transient Reactor Test Facility (TREAT). The TREAT hodoscope serves as the primary Fuel Motion Monitoring System for documenting real time fuel displacement during transient experiments. The detectors in the hodoscope have stood dormant for over 20 years and significant degradation must be addressed before the system can be brought back to operational status. The refurbishment process begins by decoupling the PRS from their matched photo multiplier tubes (PMTs) and treating the PRS with ethanol. This process cleans the surfaces, removing paint and legacy labels/ markings. During this procedure many physical variations can be observed. After cleaning, the PRS are physically measured using a digital caliper and the dimensions documented. Following this, a well-controlled 280nm LED light source is used to stimulate the PRS to produce an emission spectrum inside an integration sphere. This emission spectrum is then measured using a UV enhanced optical spectrometer. Spectral measurements are recorded from 185 nm to 580 nm in 0.4 nm steps. The PRS are then lightly sanded on the non-PMT mating surfaces and painted with commercially available reflective paint. A final emission spectrum is recorded for each PRS after painting.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
Spectral Reconstruction from Compton Crosstalk Applied to Large PVT Scintillators, STL-008-17, Year 1 of 1
Presentation addresses preliminary simulations of gamma absorption by plastic scintillators and suggests that improved sensitivity and energy resolution could be achieved by high-Z metal doping of the plastic and by implementing a Compton reconstruction algorithm on the data stream.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Scintillator Evaluations: Long-Range Blur
Presentation describes evaluations of LYSO and long range blur on a Platts flash source, including source simulation, scintillator simulation, long range blur in monolithic LYSO, and data comparison.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗