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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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NASA NTRS2003

EOS Aqua AMSR-E Arctic Sea Ice Validation Program: Arctic2003 Aircraft Campaign Flight Report

In March 2003 a coordinated Arctic sea ice validation field campaign using the NASA Wallops P-3B aircraft was successfully completed. This campaign was part of the program for validating the Earth Observing System (EOS) Aqua Advanced Microwave Scanning Radiometer (AMSR-E) sea ice products. The AMSR-E, designed and built by the Japanese National Space Development Agency for NASA, was launched May 4, 2002 on the EOS Aqua spacecraft. The AMSR-E sea ice products to be validated include sea ice concentration, sea ice temperature, and snow depth on sea ice. This flight report describes the suite of instruments flown on the P-3, the objectives of each of the seven flights, the Arctic regions overflown, and the coordination among satellite, aircraft, and surface-based measurements. Two of the seven aircraft flights were coordinated with scientists making surface measurements of snow and ice properties including sea ice temperature and snow depth on sea ice at a study area near Barrow, AK and at a Navy ice camp located in the Beaufort Sea. Two additional flights were dedicated to making heat and moisture flux measurements over the St. Lawrence Island polynya to support ongoing air-sea-ice processes studies of Arctic coastal polynyas. The remaining flights covered portions of the Bering Sea ice edge, the Chukchi Sea, and Norton Sound.

Cavalieri, D. J.↗
NASA NTRS2004

Measurements of K Shell Emission of Highly Charged Ions with the XRS at EBIT

The XRS/EBIT is a 32 channel microcalorimeter spectrometer operating at the electron beam ion trap (EBIT) facility at Lawrence Livermore National Laboratory. The system contains a flight candidate detector array from the XRS instrument for the Astro-E2 mission. The detector array in the XRS/EBIT is functionally identical to the flight array integrated into the XRS instrument and benefits from the enormous amount of calibration data from the XRS program. Since the XRSEBIT was upgraded with the new detector array in October 2003, the system has been used for a number of experiments including a survey of the K shell emission from He-like and H-like O, Ne, Ar, Fe, Ni and Kr as well as for L shell emission to measure the 3C/3D line ratio in Ni. Here we present some basic operational parameters of the instrument as well as direct excitation and simulated maxwellian spectra of He-like and E-like Fe. We show that the XRS instrument can resolve the Lyal and Lya2 lines from each other as well as from the dielectronic recombination satellites in thermal H-like Fe. We also show exactly how well the XRS instrument on Astro-E2 will resolve the thermal He-like triplet in collisionally excited Fe. This work was funded under NASA's Research Opportunities in Space Science program.

Porter, F. Scott↗
NASA NTRS1998

Detailed characterization of the 1087 MeV/nucleon iron-56 beam used for radiobiology at the alternating gradient synchrotron

We report beam characterization and dosimetric measurements made using a 56Fe beam extracted from the Brookhaven National Laboratory Alternating Gradient Synchrotron (AGS) with a kinetic energy of 1087 MeV/nucleon. The measurements reveal that the depth-dose distribution of this beam differs significantly from that obtained with a 600 MeV/nucleon iron beam used in several earlier radiobiology experiments at the Lawrence Berkeley National Laboratory's BEVALAC. We present detailed measurements of beam parameters relevant for radiobiology, including track- and dose-averaged linear energy transfer (LET), fragment composition and LET spectra measured behind sample holders used in irradiations of biological samples. We also report measurements of fluence behind three depths (1.94, 4.68 and 9.35 g cm(-2)) of polyethylene targets with the 1087 MeV/nucleon beam, and behind 1.94 g cm(-2) of polyethylene with a 610 MeV/nucleon beam delivered by the AGS. These results are compared to earlier measurements with the 600 MeV/nucleon beam at the BEVALAC.

NASA Discipline Radiation Health↗
NASA NTRS1997

Anterior segment sparing to reduce charged particle radiotherapy complications in uveal melanoma

PURPOSE: The purpose of this investigation is to delineate the risk factors in the development of neovascular glaucoma (NVG) after helium-ion irradiation of uveal melanoma patients and to propose treatment technique that may reduce this risk. METHODS AND MATERIALS: 347 uveal melanoma patients were treated with helium-ions using a single-port treatment technique. Using univariate and multivariate statistics, the NVG complication rate was analyzed according to the percent of anterior chamber in the radiation field, tumor size, tumor location, sex, age, dose, and other risk factors. Several University of California San Francisco-Lawrence Berkeley National Laboratory (LBNL) patients in each size category (medium, large, and extralarge) were retrospectively replanned using two ports instead of a single port. By using appropriate polar and azimuthal gaze angles or by treating patients with two ports, the maximum dose to the anterior segment of the eye can often be reduced. Although a larger volume of anterior chamber may receive a lower dose by using two ports than a single port treatment. We hypothesize that this could reduce the level of complications that result from the irradiation of the anterior chamber of the eye. Dose-volume histograms were calculated for the lens, and compared for the single and two-port techniques. RESULTS: NVG developed in 121 (35%) patients. The risk of NVG peaked between 1 and 2.5 years posttreatment. By univariate and multivariate analysis, the percent of lens in the field was strongly correlated with the development of NVG. Other contributing factors were tumor height, history of diabetes, and vitreous hemorrhage. Dose-volume histogram analysis of single-port vs. two-port techniques demonstrate that for some patients in the medium and large category tumor groups, a significant decrease in dose to the structures in the anterior segment of the eye could have been achieved with the use of two ports. CONCLUSION: The development of NVG after helium-ion irradiation is correlated to the amount of lens, anterior chamber in the treatment field, tumor height, proximity to the fovea, history of diabetes, and the development of vitreous hemorrhage. Although the influence of the higher LET deposition of helium-ions is unclear, this study suggests that by reducing the dose to the anterior segment of the eye may reduce the NVG complications. Based on this retrospective analysis of LBNL patients, we have implemented techniques to reduce the amount of the anterior segment receiving a high dose in our new series of patients treated with protons using the cyclotron at the UC Davis Crocker Nuclear Laboratory (CNL).

NASA Discipline Radiation Health↗
NASA NTRS2004

Removing Spectral Diagnostics of Galactic and Stellar X-Ray Emission from Charged Exchange Recombination

Our research uses the electron beam ion trap (EBIT) at the Lawrence Livermore National Laboratory to study X-ray emission from the charge exchange (CX) of highly charged ions with neutral gases. The resulting data help to fill a void in existing experimental and theoretical understanding of this atomic physics process, and are needed to explain all or part of the observed X-ray emission from the soft X-ray background, stellar winds, the Galactic Center and Galactic Ridge, supernova ejecta, and photoionized nebulae. Appreciation of the astrophysical relevance of our work continues to grow with the publication of roughly a dozen papers in the past four years describing Chandra and XMM observations of geocoronal and heliospheric CX emission, the temporal variation of such emission and correlation with X-ray emission enhancements observed by ROSAT, the theoretical spatial distribution of that emission, and CX emission around other stars. A similar number of papers were also published during that time describing CX emission from planets and comets. We expect that the launch of ASTRSE2, with its second-generation XRS microcalo- (with 6-eV resolution), will reveal even more clearly the contributions of CX to astrophysical emission. In our EBIT work we collected CX spectra from such ions as H-like and He-like Ne, Ar, and Fe. Our early measurements were made with a high-purity Ge detector, but during the second year we began operation of the first-generation XRS microcalorimeter (a twin of the XRS on ASTRO-E) and greatly improved the resolution of our measurements from roughly 150 eV (FWHM) with the Ge detectors to 10 eV with the XRS. We found that saturation of the XRS counting apparatus, which we described in our proposal as a potential concern, is not a problem for studying CX. During the course of our research, we expanded the number of injection gases permitted by the LLNL safety team, purchased and eventually operated an atomic H source, and clearly demonstrated the feasibility of our longer-range plan. For example, we successfully injected He into EBIT (not a small feat because of the difficulty of maintaining a good vacuum with He and avoiding electrical breakdown) to collect a H-like oxygen CX spectrum. The highest energy CX spectrum recorded with the XRS to date is that of the Ar K-shell emission. These measurements provided the first observation of the relative intensity ratios of resolved He-like singlet and triplet n=2->1 lines. We also carried out measurements of He-like Ne as a function of collision energy (i.e., ion temperature). Significant differences in the resulting x-ray spectra were noted. In all cases, the intensity of high-n H-like Lyman lines is significantly higher than current theoretical CX models predict.

Wargelin, Brad↗
NASA NTRS1995

A Green's function method for heavy ion beam transport

The use of Green's function has played a fundamental role in transport calculations for high-charge high-energy (HZE) ions. Two recent developments have greatly advanced the practical aspects of implementation of these methods. The first was the formulation of a closed-form solution as a multiple fragmentation perturbation series. The second was the effective summation of the closed-form solution through nonperturbative techniques. The nonperturbative methods have been recently extended to an inhomogeneous, two-layer transport media to simulate the lead scattering foil present in the Lawrence Berkeley Laboratories (LBL) biomedical beam line used for cancer therapy. Such inhomogeneous codes are necessary for astronaut shielding in space. The transport codes utilize the Langley Research Center atomic and nuclear database. Transport code and database evaluation are performed by comparison with experiments performed at the LBL Bevalac facility using 670 A MeV 20Ne and 600 A MeV 56Fe ion beams. The comparison with a time-of-flight and delta E detector measurement for the 20Ne beam and the plastic nuclear track detectors for 56Fe show agreement up to 35%-40% in water and aluminium targets, respectively.

NASA Discipline Radiation Health↗
NASA NTRS1994

Monte Carlo approach in assessing damage in higher order structures of DNA

We have developed a computer monitor of nuclear DNA in the form of chromatin fibre. The fibres are modeled as a ideal solenoid consisting of twenty helical turns with six nucleosomes per turn. The chromatin model, in combination with are Monte Carlo theory of radiation damage induces by charged particles, based on general features of tack structure and stopping power theory, has been used to evaluate the influence of DNA structure on initial damage. An interesting has emerged from our calculations. Our calculated results predict the existence of strong spatial correlations in damage sites associated with the symmetries in the solenoidal model. We have calculated spectra of short fragments of double stranded DNA produced by multiple double strand breaks induced by both high and low LET radiation. The spectra exhibit peaks at multiples of approximately 85 base pairs (the nucleosome periodicity), and approximately 1000 base pairs (solenoid periodicity). Preliminary experiments to investigate the fragment distributions from irradiated DNA, made by B. Rydberg at Lawrence Berkeley Laboratory, confirm the existence of short DNA fragments and are in substantial agreement with the predictions of our theory.

Non-NASA Center↗
NASA NTRS2005

High-Resolution Electron Energy-Loss Spectroscopy (HREELS) Using a Monochromated TEM/STEM

A 200 keV FEI TF20 XT monochromated (scanning) transmission electron microscope funded by NASA's SRLIDAP program is undergoing installation at Lawrence Livermore National Laboratory. Instrument specifications in STEM mode are Cs =1.0 mm, Cc =1.2 mm, image resolution =0.18 nm, and in TEM mode Cs =1.3 mm, Cc =1.3 mm, information limit =0.14 nm. Key features of the instrument are a voltage-stabilized high tension (HT) supply, a monochromator, a high-resolution electron energy-loss spectrometer/energy filter, a high-resolution annular darkfield detector, and a solid-state x-ray energy-dispersive spectrometer. The high-tension tank contains additional sections for 60Hz and high frequency filtering, resulting in an operating voltage of 200 kV plus or minus 0.005V, a greater than 10-fold improvement over earlier systems. The monochromator is a single Wien filter design. The energy filter is a Gatan model 866 Tridiem-ERS high resolution GIF spec d for less than or equal to 0.15 eV energy resolution with 29 pA of current in a 2 nm diameter probe. 0.13 eV has already been achieved during early installation. The x-ray detector (EDAX/Genesis 4000) has a take-off angle of 20 degrees, an active area of 30 square millimeters, and a solid angle of 0.3 steradians. The higher solid angle is possible because the objective pole-piece allows the detector to be positioned as close as 9.47 mm from the specimen. The voltage-stabilized HT supply, monochromator and GIF enable high-resolution electron energy-loss spectroscopy (HREELS) with energy resolution comparable to synchrotron XANES, but with approximately 100X better spatial resolution. The region between 0 and 100 eV is called the low-loss or valence electron energy-loss spectroscopy (VEELS) region where features due to collective plasma oscillations and single electron transitions of valence electrons are observed. Most of the low-loss VEELS features we are detecting are being observed for the first time in IDPs. A major focus of our research is to understand the origin and significance of these features and how they might be exploited to gain insight about IDPs and other meteoritic materials.

Sai, Z. R.↗
NASA NTRS2005

STS-114 Flight Day 1 Highlights

Video coverage of NASA's Return to Flight begins with the pre-flight meal and suit-up of the STS-114 crew (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda), and its departure for the launch pad on the Astrovan. The astronauts board Space Shuttle Discovery and are seated. Arms on the launch pad's Fixed Service Structure pull away, and Discovery is shown from liftoff through booster separation. Video of the ascent from a new camera onboard the External Tank (ET) is included, which features views of the ET's bipod and the tank's separation from the orbiter, with Earth in the background. During a change of shift at Mission Control Center, staff members congratulate the Shuttle crew, and Commander Collins thanks them.

Source record↗
NASA NTRS2005

STS-114 Flight Day 4 Highlights

Video coverage of Day 4 continues the Return to Flight mission of STS-114. The crew of Space Shuttle Discovery (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda) and the Expedition 11 crew (Commander Sergei Krikalev and NASA ISS Science Officer and Flight Engineer John Phillips) of the International Space Station (ISS) cooperated on several activities. These were the installation of the Raffaello Multipurpose Logistics Module onto the Common Bearthing Mechanism of the Unity module of the ISS by the Space Station Remote Manipulator System, an interview of Collins and Thomas, primarily focusing on foam shedding and shuttle safety, and use of the Orbiter Boom Sensor System by the Shuttle Remote Manipulator System to follow up on ground-based inspection of the thermal protection beneath Discovery.

Source record↗
NASA NTRS2005

STS-114 Flight Day 5 Highlights

Highlights of Day 5 of the STS-114 Return to Flight mission (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda) include video coverage of an extravehiclular activity (EVA) by Noguchi and Robinson. The other crew members of Discovery are seen on the flight deck and mid-deck helping the astronauts to suit-up. The objectives of the EVA are to test repair techniques on sample tiles in the shuttle's payload bay, to repair electrical equipment for a gyroscope on the International Space Station (ISS), and to install a replacement GPS antenna on the ISS. Noguchi and Robinson use a caulk gun and a putty knife to repair the sample tiles. The video contains several Earth views, including one of Baja California.

Source record↗
NASA NTRS2005

STS-114 Flight Day 3 Highlights

Video coverage of Day 3 includes highlights of STS-114 during the approach and docking of Discovery with the International Space Station (ISS). The Return to Flight continues with space shuttle crew members (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda) seen in onboard activities on the fore and aft portions of the flight deck during the orbiter's approach. Camarda sends a greeting to his family, and Collins maneuvers Discovery as the ISS appears steadily closer in sequential still video from the centerline camera of the Orbiter Docking System. The approach includes video of Discovery from the ISS during the orbiter's Rendezvous Pitch Maneuver, giving the ISS a clear view of the thermal protection systems underneath the orbiter. Discovery docks with the Destiny Laboratory of the ISS, and the shuttle crew greets the Expedition 11 crew (Commander Sergei Krikalev and NASA ISS Science Officer and Flight Engineer John Phillips) of the ISS onboard the station. Finally, the Space Station Remote Manipulator System hands the Orbiter Boom Sensor System to its counterpart, the Shuttle Remote Manipulator System.

Source record↗
NASA NTRS2005

STS-114 Flight Day 6 Highlights

Day 6 is a relatively quiet day for the STS-114 crew. The main responsibility for crew members of Space Shuttle Discovery (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda) and the Expedition 11 crew of the International Space Station (ISS) (Commander Sergei Krikalev and NASA ISS Science Officer and Flight Engineer John Phillips) is to unload supplies from the shuttle payload bay and from the Raffaello Multipurpose Logistics Module onto the ISS. Several of the astronauts answer interview questions from the news media, with an emphasis on the significance of their mission for the Return to Flight, shuttle damage and repair, and the future of the shuttle program. Thomas announces the winners of an essay contest for Australian students about the importance of science and mathematics education. The video includes the installation of a stowage rack for the Human Research Facility onboard the ISS, a brief description of the ISS modules, and an inverted view of the Nile Delta.

Source record↗
NASA NTRS2005

STS-114 Flight Day 2 Highlights

Video coverage of NASA's Return to Flight continues with highlights from Day 2 of STS-114. After a wake-up song from Mission Control Center, the crew of Space Shuttle Discovery (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda) inspects the orbiter for damage using a camera on the Shuttle Remote Manipulator System (SRMS). The SRMS, a robot arm, extends its length by grappling the new Orbiter Boom Sensor System, in order to image Discovery's wing leading edges and the underside of its nose. After the boom is stowed in the payload bay, the top and sides of the crew cabin are then imaged, including the Reaction Control System jets. The Shuttle's Ku-band antenna is then deployed. The video includes scenes of the payload bay contents, and crew members on the flight deck.

Source record↗
NASA NTRS2005

STS-114 Flight Day 7 Highlights

The main event of Day 7 is an extravehicular activity (EVA) to remove a failed Control Moment Gyroscope (CMG) from the Z1 Truss of the International Space Station (ISS) (Commander Sergei Krikalev and NASA ISS Science Officer and Flight Engineer John Phillips), and install a replacement stored in the payload of Space Shuttle Discovery (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda). Discovery astronauts Noguchi and Robinson are assisted in suit-up by their fellow crew members, Noguchi is carried by the Space Station Remote Manipulator System between Discovery's payload bay and the Z1 truss in order to exchange the gyroscopes with help from the pistol grip tool. Mission Control speaks to him during the EVA in order to troubleshoot the power and data connectors for new CMG. When back in the open payload bay, Noguchi and Robinson pose for pictures of each other and the Earth.

Source record↗
NASA NTRS2005

STS-114 Flight Day 8 Highlights

The major activities of Day 8 for the STS-114 crew of the Space Shuttle Discovery (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda) and the Expedition 11 crew of the International Space Station (ISS) (Commander Sergei Krikalev and NASA ISS Science Officer and Flight Engineer John Phillips) are a press conference and a conversation with President Bush. The two crews are interviewed by American, Japanese, and Russian media. Discovery crew members on the shuttle's mid-deck review paperwork regarding the impending extravehicular activity (EVA) to remove gap fillers from underneath the orbiter, and the Space Station Remote Manipulator System grapples the External Stowage Platform-2 in the Shuttle's payload bay. Finally, Mission control grants the shuttle crew some time off.

Source record↗
NASA NTRS2005

STS-114 Flight Day 9 Highlights

The highlight of Day 9 is the third extravehicular activity (EVA) of the STS-114 mission (Commander Eileen Collins, Pilot James Kelly, Mission Specialists Soichi Noguchi, Stephen Robinson, Andrew Thomas, Wendy Lawrence, and Charles Camarda). Astronauts Noguchi and Robinson are seen preparing for the EVA in the closed payload bay of Space Shuttle Discovery; on the EVA they install on the International Space Station (ISS) a Materials on the International Space Station Experiments (MISSE) unit, an External Stowage Platform (ESP-2), and a wireless antenna. The astronauts are seen working on the ISS under different lighting conditions, and use a pistol-grip tool to remove ESP-2 from the shuttle payload bay. The Space Station Remote Manipulator System then carries Robinson to the underside of the Discovery orbiter, where he communicates with Mission Control during the delicate and unprecedented removal of gap fillers from between the shuttle's tiles. Before and the after the EVA the video includes views of a damaged thermal blanket beneath the shuttle cockpit window. Other views of the shuttle include pans along the underside and topside by the Orbiter Boom Sensor System. The video also includes a view from orbit of Kazakhstan.

Source record↗
NASA NTRS2001

Virtual Reality Used to Serve the Glenn Engineering Community

There are a variety of innovative new visualization tools available to scientists and engineers for the display and analysis of their models. At the NASA Glenn Research Center, we have an ImmersaDesk, a large, single-panel, semi-immersive display device. This versatile unit can interactively display three-dimensional images in visual stereo. Our challenge is to make this virtual reality platform accessible and useful to researchers. An example of a successful application of this computer technology is the display of blade out simulations. NASA Glenn structural dynamicists, Dr. Kelly Carney and Dr. Charles Lawrence, funded by the Ultra Safe Propulsion Project under Base R&T, are researching blade outs, when turbine engines lose a fan blade during operation. Key objectives of this research include minimizing danger to the aircraft via effective blade containment, predicting destructive loads due to the imbalance following a blade loss, and identifying safe, cost-effective designs and materials for future engines.

Carney, Dorothy V.↗