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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 523 records · Page 29
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

STS-37 Mission Overview: Lead Flight Director Briefing

This NASA Kennedy Space Center (KSC) video release presents a Johnson Space Center (JSC) press conference featuring Chuck Shaw, Lead Flight Director discussing the STS-37 Atlantis shuttle mission. Topics presented include overall mission objectives, flight crew, flight directors, primary payload (Gamma Ray Observatory (GRO)), Extravehicular Activities (EVA) Development Flight Experiment (EDFE), secondary payloads, Development Test Objectives (DTO's), Detailed Supplementary Objectives (DSO's), and flight day activities. Certain flight day activities including the Gamma Ray Observatory deployment and EVA movements and translations are presented as computerized simulations. The video ends with a summary of the key points of STS-37 and a question and answer period with questions posed from Johnson as well as other NASA centers. Questions include topics involving EVA safety, emergency EVA's, and what determines the day of primary payload deployment.

Source record↗
NASA NTRS1991

Mars Observer - The next Mars mission

The next mission to Mars, called Mars Observer, will be launched in September 1992. After the capture of the spacecraft by the planet and the adjustment into a low, sun-synchronous, polar-mapping orbit in late 1993, observations will continue for a Mars year (687 days). The scientific mission centers around global geoscience and climatology observations of the Mars atmosphere, surface, and interior. The seven experiments carried by the spacecraft involve gamma-ray spectroscopy, magnetometry, surface and atmospheric imaging, atmospheric sounding, laser altimetry, gravity mapping, and thermal emission spectroscopy. All experiments contain microprocessors, which will be controlled remotely from the investigator's home institution. The long planned period of continuous 24 h/day observation promises a rich harvest of global and seasonal information. Mars Observer stands between the initial exploration of Mars and the more intensive explorations, possibly involving human beings, that are only now being planned.

Albee, Arden L.↗
NASA NTRS1977

SAS-2 high-energy gamma-ray observations of the Vela pulsar. II

Analysis of additional data from SAS-2 experiment and improvements in the orbit-attitude data and analysis procedures have produced revised values for the flux from the Vela gamma-ray source. The pulsar phase plot shows two peaks, neither of which is in phase with the single radio pulse.

Thompson, D. J.↗
DOE OSTI2022

Correlating gravitational wave and gamma-ray signals from primordial black holes

Asteroid-mass primordial black holes (PBHs) can explain the observed dark matter abundance while being consistent with the current indirect detection constraints. These PBHs can produce gamma-ray signals from Hawking radiation that are within the sensitivity of future measurements by the AMEGO and e-ASTROGAM experiments. PBHs which give rise to such observable gamma-ray signals have a cosmic origin from large primordial curvature fluctuations. There must then be a companion, stochastic gravitational wave (GW) background produced by the same curvature fluctuations. We demonstrate that the resulting GW signals will be well within the sensitivity of future detectors such as LISA, DECIGO, BBO, and the Einstein Telescope. The multimessenger signal from the observed gamma-rays and GWs will allow a precise measurement of the primordial curvature perturbation that produces the PBH. Indeed, so we argue that the resulting correlation between the two types of observations can provide a smoking-gun signal of PBHs.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS2015

Goddard's Astrophysics Science Divsion Annual Report 2014

The Astrophysics Science Division (ASD, Code 660) is one of the world's largest and most diverse astronomical organizations. Space flight missions are conceived, built and launched to observe the entire range of the electromagnetic spectrum, from gamma rays to centimeter waves. In addition, experiments are flown to gather data on high-energy cosmic rays, and plans are being made to detect gravitational radiation from space-borne missions. To enable these missions, we have vigorous programs of instrument and detector development. Division scientists also carry out preparatory theoretical work and subsequent data analysis and modeling. In addition to space flight missions, we have a vibrant suborbital program with numerous sounding rocket and balloon payloads in development or operation. The ASD is organized into five labs: the Astroparticle Physics Lab, the X-ray Astrophysics Lab, the Gravitational Astrophysics Lab, the Observational Cosmology Lab, and the Exoplanets and Stellar Astrophysics Lab. The High Energy Astrophysics Science Archive Research Center (HEASARC) is an Office at the Division level. Approximately 400 scientists and engineers work in ASD. Of these, 80 are civil servant scientists, while the rest are resident university-based scientists, contractors, postdoctoral fellows, graduate students, and administrative staff. We currently operate the Swift Explorer mission and the Fermi Gamma-ray Space Telescope. In addition, we provide data archiving and operational support for the XMM mission (jointly with ESA) and the Suzaku mission (with JAXA). We are also a partner with Caltech on the NuSTAR mission. The Hubble Space Telescope Project is headquartered at Goddard, and ASD provides Project Scientists to oversee operations at the Space Telescope Science Institute. Projects in development include the Neutron Interior Composition Explorer (NICER) mission, an X-ray timing experiment for the International Space Station; the Transiting Exoplanet Sky Survey (TESS) Explorer mission, in collaboration with MIT (Ricker, PI); the Soft X-ray Spectrometer (SXS) for the Astro-H mission in collaboration with JAXA, and the James Webb Space Telescope (JWST). The Wide-Field Infrared Survey Telescope (WFIRST), the highest ranked mission in the 2010 decadal survey, is in a pre-phase A study, and we are supplying study scientists for that mission.

Caltech on the NuSTAR mission↗
DOE OSTI2023

In-beam $$\gamma $$-ray spectroscopy of $$^{94}$$Ag

Abstract A recoil-beta-tagging experiment has been performed to study the excited $$T=0$$ T = 0 and $$T=1$$ T = 1 states in the odd–odd $$N=Z$$ N = Z nucleus $$^{94}$$ 94 Ag, populated via the $$^{40}$$ 40 Ca( $$^{58}$$ 58 Ni,1p3n) $$^{94}$$ 94 Ag reaction. The experiment was conducted using the MARA recoil separator and JUROGAM3 array at the Accelerator Laboratory of the University of Jyväskylä. Through correlating fast, high-energy beta decays at the MARA focal plane with prompt $$\gamma $$ γ rays emitted at the reaction target, a number of transitions between excited states in $$^{94}$$ 94 Ag have been identified. The timing characteristics of these transitions confirm that they fall within decay sequences that feed the short-lived $$T=1$$ T = 1 ground state of $$^{94}$$ 94 Ag. The transitions are proposed to proceed within and between the sets of states with $$T=0$$ T = 0 and $$T=1$$ T = 1 . Possible correspondence between some of these transitions from analog states in $$^{94}$$ 94 Pd has been discussed, and shell-model calculations including multipole and monopole electromagnetic effects have been presented, in order to enable predictions of the decay patterns between the $$T=0$$ T = 0 and $$T=1$$ T = 1 states and to allow a theoretical set of Coulomb energy differences to be calculated for the $$A = 94$$ A = 94 $$T=1$$ T = 1 analog states.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1982

Observations of a weak gamma ray burst, A0535 plus 26, NP0532 and solar flare events by a balloon-borne detector array

Observations of a cosmic gamma ray burst of about 10 to the -6 erg/sq cm, pulsed emission profiles of A0535 plus 26 and NP0532, and two solar flare events are reported for several energy intervals in 45-500 keV. The measurements were made with a NaI (Tl) detector array flown on a balloon to 4 g/sq cm residual atmosphere from Palestine, Texas Oct. 6-8, 1980 for 28 hours. The detector is a prototype of the Burst and Transient Source Experiment to be flown on the Gamma Ray Observatory.

Wilson, R. B.↗
NASA NTRS1992

BATSE flare observations in Solar Cycle 22

The Hard X-Ray Burst Spectrometer (HXRBS) group at GSFC has developed and is maintaining a quick-look analysis system for solar flare hard x-ray data from the Burst and Transient Source Experiment (BATSE) on the recently launched Compton Gamma-Ray Observatory (GRO). The instrument consists, in part, of 8 large planar detectors, each 2025 sq cm, placed on the corners of the GRO spacecraft with the orientation of the faces being those of a regular octahedron. Although optimized for the detection of gamma-ray bursts, these detectors are far more sensitive than any previous spacecraft-borne hard x-ray flare instrumentation both for the detection of small microflares and the resolution of fine temporal structures. The data in this BATSE solar data base are from the discriminator large area (DISCLA) rates. From each of eight detectors there are hard x-ray data in four energy channels, 25-50, 50-100, 100-300, and greater than 300 keV with a time resolution of 1.024 seconds. These data are suitable for temporal correlation with data at other wavelengths, and they provide a first look into the BATSE and other GRO instrument flare data sets. The BATSE and other GRO principle investigator groups should be contacted for the availability of data sets at higher time or spectral resolution or at higher energies.

Schwartz, R. A.↗
DOE OSTI2023

Real-time mixed reality display of dual particle radiation detector data

Radiation source localization and characterization are challenging tasks that currently require complex analyses for interpretation. Mixed reality (MR) technologies are at the verge of wide scale adoption and can assist in the visualization of complex data. Herein, we demonstrate real-time visualization of gamma ray and neutron radiation detector data in MR using the Microsoft HoloLens 2 smart glasses, significantly reducing user interpretation burden. Radiation imaging systems typically use double-scatter events of gamma rays or fast neutrons to reconstruct the incidence directional information, thus enabling source localization. The calculated images and estimated ’hot spots’ are then often displayed in 2D angular space projections on screens. By combining a state-of-the-art dual particle imaging system with HoloLens 2, we propose to display the data directly to the user via the head-mounted MR smart glasses, presenting the directional information as an overlay to the user’s 3D visual experience. We describe an open source implementation using efficient data transfer, image calculation, and 3D engine. We thereby demonstrate for the first time a real-time user experience to display fast neutron or gamma ray images from various radioactive sources set around the detector. We also introduce an alternative source search mode for situations of low event rates using a neural network and simulation based training data to provide a fast estimation of the source’s angular direction. Using MR for radiation detection provides a more intuitive perception of radioactivity and can be applied in routine radiation monitoring, education & training, emergency scenarios, or inspections.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1978

X-ray spectrometer experiment aboard the ISEE-C /Heliocentric/ spacecraft

This experiment is designed to provide continuous coverage of solar flare X-ray bursts and transient cosmic gamma-ray bursts. A proportional counter and a scintillation detector together cover the energy range from 5 to 228 keV with good sensitivity, large dynamic range, and high temporal resolution. This experiment provides data storage capability and good absolute timing so that in conjunction with similar experiments on other spacecraft, accurate source locations can be obtained for cosmic gamma-ray bursts.

Anderson, K. A.↗
NASA NTRS1992

Optical monitoring of GRO phase 1 objects

A brief overview is given of the three phases of our Gamma Ray Observatory (GRO) optical monitoring program. The acquisition of simultaneous GRO/optical data on targeted Oriented Scintillation Spectrometer Experiment (OSSE) objects, the collection of noncoincident observations of suspected GRO gamma ray emitters to determine their level of activity, and the optical imaging of burst fields in an attempt to identify the burst source are discussed. Finally, a table of future simultaneous optical observations of Phase 1 GRO targets is presented along with plans for the rapid optical imaging of gamma ray burst fields.

Mcnamara, Bernard↗
DOE OSTI2025

Compact in-vacuum gamma-ray spectrometer for high-repetition rate PW-class laser–matter interaction

With the advent of high repetition rate laser facilities, novel diagnostic tools compatible with these advanced specifications are required. This paper presents the design of an active gamma-ray spectrometer intended for these high repetition rate experiments, with particular emphasis on functionality within a PW level laser-plasma interaction chamber’s extreme conditions. The spectrometer uses stacked scintillators to accommodate a broad range of gamma-ray energies, demonstrating its adaptability for various experimental setups. In addition, it has been engineered to maintain compactness, electromagnetic pulse resistance, and ISO-5 cleanliness requirements while ensuring high sensitivity. The spectrometer has been tested in real conditions inside the PW-class level interaction chamber at the BELLA center, LBNL. The paper further details the calibration process, which utilizes a 60 Co radioactive source, and describes the unfolding technique implemented through a stochastic minimization method.

47 OTHER INSTRUMENTATION↗
NASA NTRS1991

Predicted performance of the lithium scattering and graphite crystal polarimeter for the Spectrum-X-Gamma mission

X-ray scattering from a lithium disk and Bragg reflection from a mosaic graphite crystal can be exploited to measure the linear polarization of radiation emitted from cosmic X-ray sources. The sensitivity is greatly enhanced if these polarimeters are placed at the focus of an X-ray telescope. Such devices form two of the three components of the Stellar X-Ray Polarimeter experiment scheduled to fly on the Spectrum-X-Gamma mission. The experiment will reside at the focus of one of the SODART X-ray telescopes. The expected on-axis performance of these two components of the Stellar X-Ray Polarimeter experiment based on detailed Monte-Carlo simulation is described. Various systematic effects, both external and internal to the experiment, that must be considered in order to properly design and utilize the experiment are also discussed.

Weisskopf, M. C.↗
NASA NTRS2004

Elemental Composition Variations for Large Dusty and Rocky Regions on Mars Using Gamma-Ray Data from the Mars Odyssey Gamma-Ray Spectrometer

The Gamma-Ray Spectrometer (GRS) on the Mars Odyssey spacecraft has been mapping the elemental composition of the surface materials since June 2002. To study elemental composition variations on the martian surface, seven large regions of Mars were selected: three very dusty ones and four mainly rocky ones. Large regions were used to get good counting statistics on as many gamma-ray peaks as possible from spectrum accumulated by the GRS experiment on Mars Odyssey, including elements with poor counting statistics. Data from TES were used to help select these regions. Gamma-ray peaks for several elements were analyzed. Some results and trends are reported.

Evans, L. G.↗
NASA NTRS1968

The Use of Large Lithium-Drifted, Germanium Diodes for Gamma-Ray Spectral Measurements at Balloon Altitudes

A series of balloon-borne experiments has been initiated at the Oak Ridge National Laboratory (ORNL) in cooperation with the Space Sciences Laboratory of the NASA G. C. Marshall Space Flight Center to determine the feasibility of using large (greater than 20 cc) lithium-drifted, germanium diodes to investigate the spectrum of atmospheric gamma rays (60 keV < E < 1.5 MeV) at altitudes corresponding to a few grams per cm (sup 2) residual atmosphere. The results of these measurements will also provide a basis for designing an appropriate shield for a multi-diode, highly directional gamma-ray spectrometer for use in astrophysical measurements. Two flights were accomplished during 1967 using the same two diodes and basic instrument package. Both flights were launched at the NCAR Scientific Balloon Flight Base, Palestine, Texas, and attained a float altitude of 117, 000 ft. The measured atmospheric gamma-ray spectrum shows at least one distinct line at 511 keV (annihilation radiation) superimposed on a continuous distribution of gamma rays attributable to both energy-degraded gamma rays and brems-strahlung photons. A second diode, encased in a passive shield of plastic and lead, shows the expected lines resulting from both neutron inelastic scattering and capture in the germanium. Data acquisition was accomplished on an event-by-event basis through the use of 512-channel, on-board ADC and word-generator circuits and a ground-based, on-line telemetry decoder. The decoder makes it possible to store the data in the memory of a modified pulse-height analyzer simultaneously with storage on magnetic tape. This provides a real-time visual observation of the data as it is accumulated and greatly facilitates preflight calibrations.

Chapman, G. T.↗
DOE OSTI2023

AFRRI TRIGA Reactor Neutron and Gamma Dose Characterization Preliminary Results

Integral Experiment Request (IER) 484 is part of a series of dose characterization and nuclear accident dosimeter (NAD) exercises performed under the Department of Energy (DOE) Nuclear Criticality Safety Program (NCSP). The Armed Forces Radiobilogy Research Institute (AFRRI) 1.1 MW Training, Research, Isotopes, General Atomics (TRIGA) Mark-F reactor is the third facility to undergo a dose study to establish reference dose values. A preliminary measurement was performed earlier this year, where a variety of foils were irradiated and activation gamma rays were measured using a high-purity germanium (HPGe) detector. The data was taken and analyzed to calculate the neutron spectrum in the irradiation facility. This paper will present preliminary results of the neutron dose measured. The characterization of the AFRRI dose field is planned in August.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1992

A search for luminosity - Spectral hardness correlations in SIGNE gamma-ray burst data

We use simple 2-parameter models to fit gamma-ray burst spectra from the SIGNE experiments aboard the Venera 13 and 14 spacecraft in order to estimate burst luminosity and spectral hardness. We then look for correlations between these two parameters. The hardness is characterized by kT and Ec for thermal bremsstrahlung and thermal synchrotron fits, respectively. The spectra are integrated over 1/2 s or longer, depending on photon statistics. We find that generally luminosity increases with spectral hardness. We fit power laws of the form L varies as kT sup gamma to 12 bursts. A wide range of indices with gamma = 0.5-2.5 is found, broader than that reported by Golenetskii et al. (1983).

Kargatis, Vincent E.↗