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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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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Fielding the LANL Gas Cherenkov Detector (GCD-3) at the National Ignition Facility: The engineering challenges of designing, analyzing, fabricating, testing, and commissioning the next-generation GCD detector and WellDIM3.9m insertion manipulator for use at NIF

We report that fielding the LANL third-generation Gas Cherenkov Detector (GCD-3) at the National Ignition Facility (NIF) revealed an array of complex engineering challenges. Fielding the GCD-3 Detector in a 3.9 meter re-entrant Well on the NIF Target Chamber required the development of a specialized detector deployment system named the WellDIM3.9m Diagnostic Manipulator (WellDIM). The most stringent design requirement entailed a no-load/no-contact condition with the Well, which dictated that all seismic loads be transferred to the Target Chamber port flange. The WellDIM transports the GCD-3 into the Well at a distance of 3.9m from Target Chamber Center. Finally, the GCD-3 Detector, outfitted with additional shielding to mitigate higher NIF backgrounds, will serve as a prototype for the future, heavily shielded “Super-GCD”.

42 ENGINEERING↗
DOE OSTI2016

Gamma ray measurements at OMEGA with the newest gas Cherenkov Detector “GCD-3”

Initial results from the newest Gas Cherenkov Detector (GCD-3) are reported demonstrating improved performance over previous GCD iterations. Increased shielding and lengthening of the Cherenkov photon optical path have resulted in a diminished precursor signal with increased temporal separation between the precursor and the primary DT Cherenkov signal. Design changes resulted in a measured GCD-3 sensitivity comparable to GCD-1 at identical 100 psia CO 2 operation. All metal gasket seals and pressure vessel certification to 400 psia operation allow for a GCD-3 lower Cherenkov threshold of 1.8 MeV using the fluorinated gas C 2 F 6 as compared to the 6.3 MeV lower limit of GCD-1 and GCD-2. Calibration data will be used to benchmark GEANT4 and ACCEPT detector models. Lastly, the GCD-3 acts as a prototype for the Super GCD being fielded at the National Ignition Facility (NIF) as part of the National Diagnostics Plan and will be installed at NIF in early 2016.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1977

On the equivalence of polynomial GCD and squarefree factorization problems

It is shown that a closer reexamination of Yun's 1976 paper reveals the reducibility of SQFR to GCD. The natural question that follows is whether GCD is reducible to SQFR. That is answered affirmatively and the derivation actually suggests an algorithm for computing GCD's when input polynomials are already represented by their SQFR form.

Yun, D. Y. Y.↗
DOE OSTI2023

NucD-24 Nuclear Diagnostics Development: Time resolved 12 C-rhoR on GCD and NIS technology development for polar LOS and data quality [Slides]

The Neutron Imaging team is readying for the NIS2 polar LOS development and future improvements to data quality on all LOS given consistently higher yields at NIF. Next-gen nano guide scintillators for NIS2 and CMOS cameras to replace outdated CCDs will be studied. Digital image plates will be tested for better data quality on passive imaging systems. The transition into the ignition regime is expected to show a significant signature in the ablator areal density. In the marginal ignition regime, a decrease of 12C-rhoR (ablator areal density) is expected but once the burn propagation produces a shock and compresses the ablator the trend reverses. GCD with the PD-PMT can resolve this effect in the ablator areal density by a temporal shift in the carbon signal. To give quantitative results a calibration of the detector for the Hohlraum/TMP signal is needed. Shots using Al, Si, and Au pucks will yield the needed information to move forward with this project.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

GCD: Current Performance / Issues [Slides]

LANL purchased a man instrument (pulse dilation PMT) from the Sydor Instruments, Inc. The company requests to get experimental data obtained using the instrument, for their record.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS2014

GCD TechPort Data Sheets Thermal Protection System Materials (TPSM) Project

The Thermal Protection System Materials (TPSM) Project consists of three distinct project elements: the 3-Dimensional Multifunctional Ablative Thermal Protection System (3D MAT) project element; the Conformal Ablative Thermal Protection System (CA-TPS) project element; and the Heatshield for Extreme Entry Environment Technology (HEEET) project element. 3D MAT seeks to design, develop and deliver a game changing material solution based on 3-dimensional weaving and resin infusion approach for manufacturing a material that can function as a robust structure as well as a thermal protection system. CA-TPS seeks to develop and deliver a conformal ablative material designed to be efficient and capable of withstanding peak heat flux up to 500 W/ sq cm, peak pressure up to 0.4 atm, and shear up to 500 Pa. HEEET is developing a new ablative TPS that takes advantage of state-of-the-art 3D weaving technologies and traditional manufacturing processes to infuse woven preforms with a resin, machine them to shape, and assemble them as a tiled solution on the entry vehicle substructure or heatshield.

HEEET↗
NASA NTRS2022

Mission Radiation Environment Modeling and Analysis: Avionics Trade Study for GCD Rad-Neuro Project

The two main objectives of this trade study are characterizing the mission radiation environment for multiple Design Reference Missions (DRM) and analysis of radiation effects on avionics with the goal of producing radiation tolerant Neuromorphic Computing processor chips with innovative radiation-induced fault mitigation. The NASA process for defining radiation requirements for flight avionics is applied to this domain. The effects of trapped protons and electrons in the Van Allen radiation belts predominates in Low-Earth-Orbit (LEO) and the solar wind, solar flares and Galactic Cosmic Rays (GCRs) are the dominant radiation challenge in the open space between the planets of our solar system. The nature and energy of the particles that cause circuit upset and failure is very different in the two regimes. Two results are produced from the radiation models: determining the Total Integrated Dose (TID) experienced by avionics for a given DRM and predicting the Single Event Effects (SEE) rates for avionics during high rate exposure. These tools are applied to existing semiconductors and can be used for predicting the radiation performance of future semiconductors based on early radiation testing of new devices.

Space Radiation↗
NASA NTRSDate not supplied

STMD-GCD Reactive Additive Manufacturing for Fourth Industrial Revolution Exploration Systems (RAMFIRE)

Elementum 3D, in partnership with NASA-MSFC under an ACO, seeks to help further increase launch performance and reduce launch and mission cost by advancing novel additively manufactured (AM) aluminum materials for large-scale complex rocket components and launch vehicle structures. The proposed outcome of this ACO is to advance large-scale directed energy deposition (DED) of highstrength aluminum alloys through process development, characterization, and testing.

RAMFIRE↗