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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

A Multiwavelength Study of the Cool Core Cluster MACS J1447.4+0827

Clusters of galaxies are outstanding laboratories for understanding the physics of supermassive black hole (SMBH) feedback. Here we present the first Chandra, Karl G. Jansky Very Large Array, and Hubble Space Telescope analysis of MACS J1447.4+0827 (z = 0.3755), one of the strongest cool core clusters known, in which extreme feedback from its central SMBH is needed to prevent the hot intracluster gas from cooling. Using this multiwavelength approach, including 70 ks of Chandra X-ray observations, we detect the presence of collimated jetted outflows that coincide with a southern and a northern X-ray cavity. The total mechanical power associated with these outflows (P {sub cav} ≈ 6 × 10{sup 44} erg s{sup −1}) is roughly consistent with the energy required to prevent catastrophic cooling of the hot intracluster gas (L {sub cool} = 1.71 ± 0.01 × 10{sup 45} erg s{sup −1} for t {sub cool} = 7.7 Gyr), implying that powerful SMBH feedback was in place several Gyr ago in MACS J1447.7+0827. In addition, we detect the presence of a radio minihalo that extends over 300 kpc in diameter (P {sub 1.4GHz} = 3.0 ± 0.3 × 10{sup 24} W Hz{sup −1}). The X-ray observations also reveal an ∼20 kpc plumelike structure that coincides with optical dusty filaments that surround the central galaxy. Overall, this study demonstrates that the various physical phenomena occurring in the most nearby clusters of galaxies are also occurring in their more distant analogs.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS1991

NASA 1990 Multisensor Airborne Campaigns (MACs) for ecosystem and watershed studies

The Multisensor Airborne Campaign (MAC) focus within NASA's former Land Processes research program was conceived to achieve the following objectives: to acquire relatively complete, multisensor data sets for well-studied field sites, to add a strong remote sensing science component to ecology-, hydrology-, and geology-oriented field projects, to create a research environment that promotes strong interactions among scientists within the program, and to more efficiently utilize and compete for the NASA fleet of remote sensing aircraft. Four new MAC's were conducted in 1990: the Oregon Transect Ecosystem Research (OTTER) project along an east-west transect through central Oregon, the Forest Ecosystem Dynamics (FED) project at the Northern Experimental Forest in Howland, Maine, the MACHYDRO project in the Mahantango Creek watershed in central Pennsylvania, and the Walnut Gulch project near Tombstone, Arizona. The OTTER project is testing a model that estimates the major fluxes of carbon, nitrogen, and water through temperate coniferous forest ecosystems. The focus in the project is on short time-scale (days-year) variations in ecosystem function. The FED project is concerned with modeling vegetation changes of forest ecosystems using remotely sensed observations to extract biophysical properties of forest canopies. The focus in this project is on long time-scale (decades to millenia) changes in ecosystem structure. The MACHYDRO project is studying the role of soil moisture and its regulating effects on hydrologic processes. The focus of the study is to delineate soil moisture differences within a basin and their changes with respect to evapotranspiration, rainfall, and streamflow. The Walnut Gulch project is focused on the effects of soil moisture in the energy and water balance of arid and semiarid ecosystems and their feedbacks to the atmosphere via thermal forcing.

Wickland, Diane E.↗
NASA NTRS1992

MAC Europe 1991: Evaluation of AVIRIS, GER imaging spectrometry data for the land application testsite Oberpfaffenhofen

During the MAC Europe 91 Campaign, the area of Oberpfaffenhofen including the land application testsite Oberpfaffenhofen was flown by the AVIRIS imaging spectrometer, the GER 2 imaging spectrometer (63 band scanner), and two SAR systems (NASA/JPL AIRSAR and DLR E-SAR). In parallel to the overflights ground spectrometry (ASD, IRIS M IV) and atmospheric measurements were carried out in order to provide data for optical sensor calibration. Ground spectrometry measurements were carried out in the runway area of the DLR research center Oberpfaffenhofen. This area was used as well during the GER 2 European flight campaign EISAC 89 as a calibration target. The land application testsite Oberpfaffenhofen is located 3 km north of the DLR research center. During the MAC Europe 91 Campaign a ground survey was carried out for documentation in the ground information data base (vegetation type, vegetation geometry, soil type, and soil mixture). Crop stands analyzed were corn, barley and rape. The DLR runway area and the land application testsite Oberpfaffenhofen were flown with the AVIRIS on 29 July and with the GER 2 on 12 and 23 July and 3 Sep. AVIRIS and GER 2 scenes were processed and atmospherically corrected for optical data analysis of optical and radar data. For the AVIRIS and the GER 2 scenes, signal-to-noise ratios (SNR) estimates were calculated. An example of the reflectance of 6 calibration targets inside a GER 2 scene of Oberpfaffenhofen is given. SNR values for the GER 2 for a medium albedo target are given. The integrated analysis for the optical and radar data was carried out in cooperation with the DLR Institute for Microwave Technologies.

Lehmann, F.↗
NASA NTRS1993

Application of MAC-Europe AVIRIS data to the analysis of various alteration stages in the Landdmannalauger Hydrothermal Area (South Iceland)

In June 1991 extensive airborne remote sensing data-sets have been acquired over Iceland in the framework of the joint NASA/ESA Multisensor Airborne Campaign Europe (MAC-Europe). The study area is located within the Torfajokull central volcanic complex in South Iceland. This complex is composed by anomalously abundant rhyolitic acid volcanics, which underwent intensive hydrothermal alteration. Detailed studies of surface alteration of rhyolitic rocks in the area showed that all the major elements are leached as the rock is affected by complex mineralogical changes. Montmorillonite appears during the earliest stages of alteration. In the ultimate alteration product montmorillonite is absent and the rock consists mostly of amorphous silica, anatase, up to a volume of 50% kaolinite and variable amounts of native sulphur and pyrite. The case study presented shall endeavor to assess the potential of MAC-Europe AVIRIS and TMS data in determining a possible zonation of hydrothermal alteration in relationship to the active geo-thermal fields and structural features. To this end, the airborne data is analysed in comparison with laboratory spectral measurements of characteristics rock, soil, and vegetation samples collected in the study areaduring the summer of 1992. Various spectral mapping algorithms as well as unmixing approaches are tested and evaluated. Detailed geological and structural mapping as well as geochemical analysis of the main rock and soil types were performed to underpin the analysis of the airborne data.

Sommer, S.↗
NASA NTRS2014

Thrust Removal Scheme for the FAST-MAC Circulation Control Model Tested in the National Transonic Facility

A second wind tunnel test of the FAST-MAC circulation control semi-span model was recently completed in the National Transonic Facility at the NASA Langley Research Center. The model allowed independent control of four circulation control plenums producing a high momentum jet from a blowing slot near the wing trailing edge that was directed over a 15% chord simple-hinged flap. The model was configured for transonic testing of the cruise configuration with 0deg flap deflection to determine the potential for drag reduction with the circulation control blowing. Encouraging results from analysis of wing surface pressures suggested that the circulation control blowing was effective in reducing the transonic drag on the configuration, however this could not be quantified until the thrust generated by the blowing slot was correctly removed from the force and moment balance data. This paper will present the thrust removal methodology used for the FAST-MAC circulation control model and describe the experimental measurements and techniques used to develop the methodology. A discussion on the impact to the force and moment data as a result of removing the thrust from the blowing slot will also be presented for the cruise configuration, where at some Mach and Reynolds number conditions, the thrust-removed corrected data showed that a drag reduction was realized as a consequence of the blowing.

Chan, David T.↗
NASA NTRS2017

Transonic Drag Reduction Through Trailing-Edge Blowing on the FAST-MAC Circulation Control Model

A third wind tunnel test of the FAST-MAC circulation control semi-span model was completed in the National Transonic Facility at the NASA Langley Research Center where the model was configured for transonic testing of the cruise configuration with 0deg flap detection to determine the potential for transonic drag reduction with the circulation control blowing. The model allowed independent control of four circulation control plenums producing a high momentum jet from a blowing slot near the wing trailing edge that was directed over a 15% chord simple-hinged ap. Recent upgrades to transonic semi-span flow control testing at the NTF have demonstrated an improvement to overall data repeatability, particularly for the drag measurement, that allows for increased confidence in the data results. The static thrust generated by the blowing slot was removed from the wind-on data using force and moment balance data from wind-o thrust tares. This paper discusses the impact of the trailing-edge blowing to the transonic aerodynamics of the FAST-MAC model in the cruise configuration, where at flight Reynolds numbers, the thrust-removed corrected data showed that an overall drag reduction and increased aerodynamic efficiency was realized as a consequence of the blowing.

Chan, David T.↗
DOE OSTI2025

NSUF FY 2024 Annual Report: Microscopy and Characterization Suite (MaCS) and National Synchrotron Light Source-II (NSLS-II)

The Microscopy and Characterization Suite (MaCS) laboratory at the Center for Advanced Energy Studies (CAES) and the National Synchrotron Light Source-II (NSLS-II) at Brookhaven National Laboratory (BNL) partner with the Nuclear Science User Facilities (NSUF). This partnership provides funding that allows researchers to access these facilities at no cost for studying irradiation effects on nuclear fuels and materials. Through NSUF, both MaCS and NSLS-II support post-irradiation examination (PIE) and irradiation activities for NSUF Rapid Turnaround Experiments (RTE) and NSUF Consolidated Innovative Nuclear Research (CINR) awards. This report details the work completed at these facilities for NSUF competitively selected awards during fiscal year 2024.

99 GENERAL AND MISCELLANEOUS↗
NASA NTRS1989

Comparison between pressure gradient method and MAC method on high Re calculation

A cavity flow driven by shear and buoyancy forces is used as a test problem in the application of a nonstaggered pressure gradient (PG) method in solving the two-dimensional incompressible Navier-Stokes equations. Twelve finite differencing schemes are used to solve the cavity flow problem. The schemes consist of various combinations of grid arrangements, upwinding treatments, and conservativeness of convection terms. An artificial source term is introduced, and the solutions are compared with those obtained by the conventional marker-and-cell (MAC) method. The comparisons favor the PG method. Numerical results obtained by the twelve schemes are compared with exact solutions in order to assess the stability and accuracy of each scheme.

Tan, C.-H.↗
NASA NTRS1991

Analysis and convergence of the MAC scheme. Part 1: The linear problem

The MAC discretization of fluid flow is analyzed for the stationary Stokes equations. It is proved that the discrete approximations do in fact converge to the exact solutions of the flow equations. Estimates using mesh dependent norms analogous to the standard H(sup 1) and L(sup 2) norms are given for the velocity and pressure, respectively.

Nicolaides, R. A.↗
NASA NTRS1991

Mineralogy and matrix composition of CR chondrites Renazzo and EET 87770, and ungrouped chondrites Essebi and MAC 87300

The fine-grained mineralogy of the matrix of two CR chondrites, Renazzo and EET 87770, and the ungrouped (but possible related) Essebi and MAC 87300 chondrites was characterized using standard microprobe (focussed beam) and transmission electron microscopy (TEM) techniques (using ultramicrotomed sections). These results are compared to previously obtained results for 31 other carbonaceous chondrites.

Zolensky, Michael E.↗
NASA NTRS1993

MAC to VAX Connectivity: Heartrate Spectral Analysis System

The heart rate Spectral Analysis System (SAS) acquires and analyzes, in real-time, the Space Shuttle onboard electrocardiograph (EKG) experiment signals, calculates the heartrate, and applies a Fast Fourier Transformation (FFT) to the heart rate. The system also calculates other statistical parameters such as the 'mean heart rate' over specific time period and heart rate histogram. This SAS is used by NASA Principal Investigators as a research tool to determine the effects of weightlessness on the human cardiovascular system. This is also used to determine if Lower Body Negative Pressure (LBNP) is an effective countermeasure to the orthostatic intolerance experienced by astronauts upon return to normal gravity. In microgravity, astronauts perform the LBNP experiment in the mid deck of the Space Shuttle. The experiment data are downlinked by the orbiter telemetry system, then processed and analyzed in real-time by the integrated Life Sciences Data Acquisition (LSDS) - Spectral Analysis System. The data system is integrated within the framework of two different computer systems, VAX and Macintosh (Mac), using the networking infrastructure to assist the investigators in further understanding the most complex machine on Earth--the human body.

Rahman, Hasan H.↗
NASA NTRS1992

Geochemistry and petrology of primitive achondrite meteorites LEW 88280, MAC 88177, ALHA 81187, EET 84302, and LEW 88663

Primitive achondrites are meteorites that have mineral and bulk chemical compositions similar to the most primitive meteorites (chondrites) but have textures similar to more evolved meteorites (achondrites). The unique geochemistry and texture of the primitive achondrites suggest these meteorites may be genetic intermediates between chondrites and achondrites and may preserve evidence of processes occurring in the early solar system. Five primitive achondrites LEW 88280, MAC 88177, ALHA 81187, EET 84302, and LEW 88663 were examined in this study in order to classify the meteorites and to determine processes that have affected them. Bulk chemical analyses of Nap, K2O, CaO, FeO, Cr, Co, Ni, Sc, Ir, Au, As, Sb, Se, Br, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu were determined for each meteorite by Instrumental Neutron Activation Analysis (INAA). Concentrations of Hf, U, and Th were determined for some meteorites. Polished thin sections of the five meteorites were examined in transmitted and reflected light microscopy to identify minerals and examine petrographic relationships. Minerals found in the meteorites include olivine, orthopyroxene, clinopyroxene, plagioclase, Cr-spinel, phosphates, troilite, kamecite, and taenite along with other minor phases. Mineral compositions were determined with an electron microprobe. The initial study suggests that the meteorites have been altered by metamorphic processes although igneous processes may also have played a role in the evolution of these rocks. Further studies of isotope and bulk chemistry are planned for these meteorites.

Field, Stephen W.↗
NASA NTRS1992

Comparison of JPL-AIRSAR and DLR E-SAR images from the MAC Europe 1991 campaign over testsite Oberpfaffenhofen: Frequency and polarization dependent backscatter variations from agricultural fields

On July 12, the MAC Europe '91 (Multi-Sensor Airborne Campaign) took place over test site Oberpfaffenhofen. The DLR Institute of Radio-Frequency Technology participated with its C-VV, X-VV, and X-HH Experimental Synthetic Aperture Radar (E-SAR). The high resolution E-SAR images with a pixel size between 1 and 2 m and the polarimetric AIRSAR images were analyzed. Using both sensors in combination is a unique opportunity to evaluate SAR images in a frequency range from P- to X-band and to investigate polarimetric information.

Schmullius, C.↗
NASA NTRS1993

Synergy between optical and microwave remote sensing to derive soil and vegetation parameters from MAC Europe 1991 Experiment

The ability of remote sensing for monitoring vegetation density and soil moisture for agricultural applications is extensively studied. In optical bands, vegetation indices (NDVI, WDVI) in visible and near infrared reflectances are related to biophysical quantities as the leaf area index, the biomass. In active microwave bands, the quantitative assessment of crop parameters and soil moisture over agricultural areas by radar multiconfiguration algorithms remains prospective. Furthermore the main results are mostly validated on small test sites, but have still to be demonstrated in an operational way at a regional scale. In this study, a large data set of radar backscattering has been achieved at a regional scale on a French pilot watershed, the Orgeval, along two growing seasons in 1988 and 1989 (mainly wheat and corn). The radar backscattering was provided by the airborne scatterometer ERASME, designed at CRPE, (C and X bands and HH and VV polarizations). Empirical relationships to estimate water crop and soil moisture over wheat in CHH band under actual field conditions and at a watershed scale are investigated. Therefore, the algorithms developed in CHH band are applied for mapping the surface conditions over wheat fields using the AIRSAR and TMS images collected during the MAC EUROPE 1991 experiment. The synergy between optical and microwave bands is analyzed.

Taconet, O.↗
NASA NTRS1993

Soil moisture retrieval in the Oberpfaffenhofen testsite using MAC Europe AIRSAR data

Soil moisture content is an important parameter in many disciplines of science like hydrology, meteorology, agriculture and others. Microwave remote sensing technique has a high potential in measuring the dielectric constant of soils, which is strongly governed by the soil moisture. Much excellent work has been done on investigating the relationship between backscattering coefficient and soil moisture. Most of these studies are measured in a laboratory or are carried out with a multitemporal data set. This means, that the variation in the backscattering coefficient is only related to the soil moisture because all other parameters influencing the backscattering like surface roughness, vegetation cover, plant geometry, phenology of plants and row direction are kept constant. In this study the sensitivity of the backscattering coefficient to soil moisture of corn fields is investigated. In the framework of the MAC-Europe Campaign in June 1991, the NASA/JPL three-frequency polarimetric AIRSAR system collected data over the test site Oberpfaffenhofen. The AIRSAR campaign in Oberpfaffenhofen was complemented with intensive ground truth measurements. The sampled corn fields are nearly in the range of the same incidence angle (approximately 20 deg) and belong to different soil types. The evaluation was carried out at a single data set. The results show that the backscattering, measured at P-band, can be described with only two parameters very well. The main parameter influencing the backscattering is the soil moisture content; the second subordinated parameter is the row direction.

Wever, Tobias↗
NASA NTRS2000

MACS, An Instrument, and a Methodology for Simulations and Global Measurements of the Coronal Electron Temperature and the Solar Wind Velocity on the Solar Corona

The determination of the radial and latitudinal temperature and wind profiles of the solar corona is of great importance in understanding the coronal heating mechanism and the dynamics of coronal expansion. Cram presented the theory for the formation of the K-coronal spectrum and identified two important observations. He observed the existence of temperature sensitive anti-nodes at certain wavelengths in the theoretical K-coronal spectra. The anti-nodes are separated by temperature-insensitive nodes. Remarkably, Cram showed that the wavelengths of the nodes and anti-nodes are almost independent of altitude above the solar limb. Because of these features, Cram suggested that the intensity ratios at two anti-nodes could be used as a diagnostic of the electron temperature in the K-corona. Based on this temperature diagnostic technique prescribed by Cram a slit-based spectroscopic study was performed by Ichimoto et al. on the solar corona in conjunction with the total solar eclipse of 3 Nov 1994 in Putre, Chile to determine the temperature profile of the solar corona. In this thesis Cram's theory has been extended to incorporate the role of the solar wind in the formation of the K-corona, and we have identified both temperature and wind sensitive intensity ratios. The instrument, MACS, for Multi Aperture Coronal Spectrometer, a fiber optic based spectrograph, was designed for global and simultaneous measurement of the thermal electron temperature and the solar wind velocity in the solar corona. The first ever experiment of this nature was conducted in conjunction with the total solar eclipse of 11 Aug 1999 in Elazig, Turkey. In this instrument one end of each of twenty fiber optic tips were positioned in the focal plane of the telescope in such a way that we could observe conditions simultaneously at many different latitudes and two different radial distances in the solar corona. The other ends of the fibers were vertically aligned and placed at the primary focus of the collimating lens of the spectrograph to obtain simultaneous and global spectra on the solar corona. By isolating the K-coronal spectrum from the spectrum recorded by each fiber the temperature and the wind sensitive intensity ratios were calculated to obtain simultaneous and global measurements of the thermal electron temperature and the solar wind velocity. We were successful in obtaining reliable estimates of the coronal temperature at many positions in the corona. This is the first time that simultaneous measurements of coronal temperatures have been obtained at so many points. However due to instrumental scattering encountered during observations, reliable estimates of the wind velocity turned out to be impossible to obtain. Although remedial measures were taken prior to observation, this task proved to be difficult owing to the inability to replicate the conditions expected during an eclipse in the laboratory. The full extent of the instrumental scattering was apparent only when we analyzed the observational sequence. Nevertheless the experience obtained from this very first attempt to simultaneously and globally measure both the wind velocity and the temperature on the solar corona have provided valuable information to conduct any future observations successfully.

Reginald, Nelson L.↗