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NGC 4945 contains a well-known heavily obscured active galactic nucleus (AGN) at its core, with prior reports of strong nuclear and off-nuclear neutral Fe K$\alpha$ emission due to the AGN activity. We report the discovery of very extended Fe K$\alpha$ emission with the XMM-Newton EPIC pn in a $\sim5$ kpc by $\sim10$ kpc region that is misaligned with the plane of the inclined optical galaxy disk by $\sim60$ degrees in projection. After a careful consideration of the crowded center of the galaxy and numerous unresolved hard X-ray sources present, we estimate that $\sim15$% of the Fe K$\alpha$ is extended on kpc-sized scales. The overall size and misalignment of the region follows an unusual pattern of radio polarization that is not typical of starbursts or normal disk galaxies but has been interpreted as possibly due to AGN activity. We suggest that the extended Fe K$\alpha$ emission arose from a period of AGN eruption several million years ago - a relic of a past AGN ejection episode., Comment: 24 pages including figures and tables, 12 figures, 3 tables. Submitted to ApJ, under review

We present an evaluation of airborne Intensity-Modulated Continuous-Wave (IM-CW) lidar measurements of atmospheric column CO2 mole fractions during the ACT-America project. This lidar system transmits online and offline wavelengths simultaneously on the 1.57111-um CO2 absorption line, with each modulated wavelength using orthogonal swept frequency waveforms. After the spectral characteristics of this system were calibrated through short-path measurements, we used the HITRAN spectroscopic database to derive the average-column CO2 mixing ratio (XCO2) from the lidar measured optical depths. Based on in situ measurements of meteorological parameters and CO2 concentrations for calibration data, we demonstrate that our lidar CO2 measurements were consistent from season to season and had an absolute calibration error (standard deviation) of 0.80 ppm when compared to XCO2 values derived from in situ measurements. By using a 10-second or longer moving average, a long-term stability of 1 ppm or better was obtained. The estimated CO2 measurement precision for 0.1-s, 1-s, 10-s, and 60-s averages were determined to be 3.4 ppm (0.84%), 1.2 ppm (0.30%), 0.43 ppm (0.10%), and 0.26 ppm (0.063%), respectively. These correspond to measurement signal-to-noise ratios of 120, 330, 950, and 1600, respectively. The drift in XCO2 over one-hour of flight time was found to be below our detection limit of about 0.1 ppm. These analyses demonstrate that the measurement stability, precision and accuracy are all well below the thresholds needed to study synoptic-scale variations in atmospheric XCO2., Comment: 20 pages, 5 figures. Submitted to Earth, Space, and Science (AGU)

In this theoretical study, modulation techniques are developed to support the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission. A CW lidar system using sine waves modulated by ML pseudo random noise codes is described for making simultaneous online/offline differential absorption measurements. Amplitude and Phase Shift Keying (PSK) modulated IM carriers, in addition to a hybrid pulse technique are investigated that exhibit optimal autocorrelation properties. A method is presented to bandwidth limit the ML sequence based on a filter implemented in terms of Jacobi theta functions that does not significantly degrade the resolution or introduce side lobes as a means of reducing aliasing and IM carrier bandwidth., Comment: Accepted for publication in Applied Optics

A system using a non-linear multi-swept sine wave system is described which employs a multi-channel, multi-swept orthogonal waves, to separate channels and make multiple, simultaneous online/offline CO2 measurements. An analytic expression and systematic method for determining the orthogonal frequencies for the unswept, linear swept and non-linear swept cases is presented. It is shown that one may reduce sidelobes of the autocorrelation function while preserving cross channel orthogonality, for thin cloud rejection., Comment: 22 pages, 11 figures. Submitted to Applied Optics on 03/06/2013

A system using a personal computer, speaker, and a microphone is used to detect objects, and make crude measurements using a carrier modulated by a pseudorandom noise (PN) code. This system can be constructed using a personal computer and audio equipment commonly found in the laboratory or at home, or more sophisticated equipment that can be purchased at reasonable cost. We demonstrate its value as an instructional tool for teaching concepts of remote sensing and digital signal processing., Comment: Accepted for publication in American Journal of Physics

The Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) CarbonHawk Experiment Simulator (ACES) is a NASA Langley Research Center instrument funded by NASA’s Science Mission Directorate that seeks to advance technologies critical to measuring atmospheric column carbon dioxide (CO2) mixing ratios in support of the NASA ASCENDS mission. The ACES instrument, an Intensity-Modulated Continuous-Wave (IM-CW) lidar, was designed for high-altitude aircraft operations and can be directly applied to space instrumentation to meet the ASCENDS mission requirements. The ACES design demonstrates advanced technologies critical for developing an airborne simulator and spaceborne instrument with lower platform consumption of size, mass, and power, and with improved performance. ACES recently flew on the NASA DC-8 aircraft during the 2017 NASA ASCENDS/Arctic-Boreal Vulnerability Experiment (ABoVE) airborne measurement campaign to test ASCENDS-related technologies in the challenging Arctic environment. Data were collected over a wide variety of surface reflectivities, terrain, and atmospheric conditions during the campaign’s 8 research flights. ACES also flew during the 2017 and 2018 Atmospheric Carbon and Transport – America (ACT-America) Earth Venture Suborbital -2 (EVS-2) campaigns along with the primary ACT-America CO2 lidar, Harris Corporation’s Multi-Frequency Fiber Laser Lidar (MFLL). Regional CO2 distributions of the lower atmosphere were observed from the C-130 aircraft during the ACT-America campaigns in support of ACT-America’s science objectives. The airborne lidars provide unique data that complement the more traditional in situ sensors. This presentation shows the applications of CO2 lidars in meeting these science needs from airborne platforms and an eventual spacecraft.

The Figure Location Test (FLT) developed by Donlon, Reilly and McKee to provide a machine-scorable test of the cognitive style called field dependence-field independence, was administered as the experimental section of the October 1976, Graduate Record Examination (GRE) Aptitude Test at about one third of the centers in the United States. Initial data analysis showed that the FLT was related to choice of majors: mathematics and chemistry having high mean scores while education, sociology, and nursing had low mean scores. In addition, those who responded that being people-related was an important consideration in choosing their major fields had lower mean scores than those who said it was unimportant. The converse was true for those who said they emphasized intellectuality. Analysis, including analysis of covariance and partial correlation to remove the effects of the GRE-Verbal and Quantitative scores, showed that most of these effects overlapped those of the other variables. That Witkin found some independent relationships between choice of major and a cognitive style test is perhaps due to the fact that he was studying undergraduate rather than graduate students, or to the fact that he was studying students in a single, rather selective, college. (Author/PN)

This study compared word association responses for college students in three geographic areas from four different kinds of colleges: (1) selective predominantly white colleges, (2) less selective predominantly white colleges, (3) selective predominantly black colleges, and (4) less selective predominantly black colleges. Stimulus words were chosen from those used in Graduate Record Examinations (GRE) verbal analogy and antonym items. Responses were tabulated separately by sex. There were a few words which evoked different responses from males and females, but geographic area apparently made no difference. A few stimulus words, mostly related to the "black experience," evoked different association patterns from students at predominantly black and predominantly white colleges, but most stimulus words yielded similar response patterns from both kinds of college. There was a comparatively high level of "no response" for those stimulus words with a Thorndike-Lorge word frequency count of nine or fewer per million counted words. This most frequently happened at the non-selective colleges, and particularly at the predominantly black non-selective colleges. It was hypothesized that most often this occurred because the student was not acquainted with the word. A number of responses seemed to come from the student having mistaken the stimulus word for one of similar appearance. (Author/RC)

The fairness of testing practices for selection or promotion of members of different racial and ethnic groups has been questioned. In this study, a search was made of occupations in the Federal Government to find those in various agencies with sufficient ethnic group representation for acceptable sample size, and for which dependable and objective criterion measures might be developed. Research conducted over a six-year period focused on the occupations of Medical Technician, Cartographic Technician, and Inventory Management Specialist. After careful job analyses, aptitude and ability test batteries were selected, several types of criterion measures were developed, and background data and job activities questionnaires were prepared. Data analysis indicated that tests found to be valid for one ethnic group were in general valid for the other ethnic groups included in the study, across occupations. Regression equations developed on majority group data appeared to predict almost equally well for minority groups, and some instances predicted higher criterion scores for minorities. The use of supervisors' ratings as a criterion of job performance in validity studies with ethnic sub-groups was called into question by findings of this study, which disclosed interaction effects ascribed to ethnic group membership of rater and ethnic group membership of ratee. (Author/BJG)

Significant atmospheric CO2 variations on various spatiotemporal scales were observed during ASCENDS flight campaigns. For example, around 10-ppm CO2 changes were found within free troposphere in a region of about 200x300 sq km over Iowa during a summer 2014 flight. Even over extended forests, about 2-ppm CO2 column variability was measured within about 500-km distance. For winter times, especially over snow covered ground, relatively less horizontal CO2 variability was observed, likely owing to minimal interactions between the atmosphere and land surface. Inter-annual variations of CO2 drawdown over cornfields in the Mid-West were found to be larger than 5 ppm due to slight differences in the corn growing phase and meteorological conditions even in the same time period of a year. Furthermore, considerable differences in atmospheric CO2 profiles were found during winter and summer campaigns. In the winter CO2 was found to decrease from about 400 ppm in the atmospheric boundary layer (ABL) to about 392 ppm above 10 km, while in the summer CO2 increased from 386 ppm in the ABL to about 396 ppm in free troposphere. These and other CO2 observations are discussed in this presentation.

Global atmospheric carbon dioxide (CO2) measurements for the NASA Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) space mission are critical for improving our understanding of global CO2 sources and sinks. Advanced Intensity- Modulated Continuous-Wave (IM-CW) lidar techniques are investigated as a means of facilitating CO2 measurements from space to meet the ASCENDS measurement requirements. In recent numerical, laboratory and flight experiments we have successfully used the Binary Phase Shift Keying (BPSK) modulation technique to uniquely discriminate surface lidar returns from intermediate aerosol and cloud contamination. We demonstrate the utility of BPSK to eliminate sidelobes in the range profile as a means of making Integrated Path Differential Absorption (IPDA) column CO2 measurements in the presence of optically thin clouds, thereby eliminating the need to correct for sidelobe bias errors caused by the clouds. Furthermore, high accuracy and precision ranging to the surface as well as to the top of intermediate cloud layers, which is a requirement for the inversion of column CO2 number density measurements to column CO2 mixing ratios, has been demonstrated using new hyperfine interpolation techniques that takes advantage of the periodicity of the modulation waveforms. This approach works well for both BPSK and linear swept-frequency modulation techniques. The BPSK technique under investigation has excellent auto-correlation properties while possessing a finite bandwidth. A comparison of BPSK and linear swept-frequency is also discussed in this paper. These results are extended to include Richardson-Lucy deconvolution techniques to extend the resolution of the lidar beyond that implied by limit of the bandwidth of the modulation, where it is shown useful for making tree canopy measurements.