Imaging Microchannel Plate Detectors For XUV Sky Survey Experiments

Air Force Geophysics Laboratory (AFGL) Infrared Sky Survey Experiments

10.1117/12.931944 ◽

1981 ◽

Cited By ~ 3

Author(s):

S. D. Price ◽

T. L. Murdock ◽

K. Shivanandan

Keyword(s):

Air Force ◽

Sky Survey ◽

Survey Experiments

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Southern Hemisphere Seti Survey: Five Years of Project Meta II

International Astronomical Union Colloquium ◽

10.1017/s0252921100015153 ◽

1997 ◽

Vol 161 ◽

pp. 611-621

Author(s):

Guillermo A. Lemarchand ◽

Fernando R. Colomb ◽

E. Eduardo Hurrell ◽

Juan Carlos Olalde

Keyword(s):

Southern Hemisphere ◽

Scattering Theory ◽

Galactic Plane ◽

Narrow Band ◽

Neutral Hydrogen ◽

Sky Survey ◽

Inertial Frames ◽

Interstellar Scattering ◽

Extraterrestrial Origin ◽

Spectral Channels

AbstractProject META II, a full sky survey for artificial narrow-band signals, has been conducted from one of the two 30-m radiotelescopes of the Instituto Argentino de Radioastronomía (IAR). The search was performed near the 1420 Mhz line of neutral hydrogen, using a 8.4 million channels Fourier spectrometer of 0.05 Hz resolution and 400 kHz instantaneous bandwidth. The observing frequency was corrected both for motions with respect to three astronomical inertial frames, and for the effect of Earths rotation, which provides a characteristic changing signature for narrow-band signals of extraterrestrial origin. Among the 2 × 1013spectral channels analyzed, 29 extra-statistical narrow-band events were found, exceeding the average threshold of 1.7 × 10−23Wm−2. The strongest signals that survive culling for terrestrial interference lie in or near the galactic plane. A description of the project META II observing scheme and results is made as well as the possible interpretation of the results using the Cordes-Lazio-Sagan model based in interstellar scattering theory.

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Effect of energy filtering on micro-diffraction in the SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017075x ◽

1994 ◽

Vol 52 ◽

pp. 604-605

Author(s):

James F. Mancuso ◽

Leo A. Fama ◽

William B. Maxwell ◽

Jerry L. Lehman ◽

Hasso Weiland ◽

...

Keyword(s):

Detection Efficiency ◽

Ccd Camera ◽

High Gain ◽

Microchannel Plate ◽

Electrostatic Energy ◽

Energy Filtering ◽

Electron Channelling ◽

Low Energy Electrons ◽

Low Sensitivity ◽

Angular Field Of View

Micro-diffraction based crystallography is essential to the design and development of many classes of ‘crafted materials’. Although the scanning electron microscope can provide crystallographic information with high spatial resolution, its current utility is severely limited by the low sensitivity of existing diffraction techniques (ref: Dingley). Previously, Joy showed that energy filtering increased contrast and pattern visibility in electron channelling. This present paper discribes the effect of energy filtering on EBSP sensitivity and backscattered SEM imaging.The EBSP detector consisted of an electron energy filter, a microchannel plate detector, a phosphor screen, optical coupler, and a slow scan CCD camera. The electrostatic energy filter used in this experiment was constructed as a cone with 5 coaxial electrodes. The angular field-of-view of the filter was approximately 38°. The microchannel plate, which was the initial sensing component, had high gain and had 50% to 80% detection efficiency for the low energy electrons that passed through the retarding field filter.

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Low - Voltage Scanning Electron Microscopy Imaging, Secondary and Backscatter, With Microchannel Plate Detector

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180963 ◽

1990 ◽

Vol 48 (1) ◽

pp. 442-442

Author(s):

Galen Powers ◽

Ray Cochran

Keyword(s):

Low Voltage ◽

Beam Current ◽

Microchannel Plate ◽

Normal Operation ◽

Microscopy Imaging ◽

Backscatter Signal ◽

Vacuum Interface ◽

Width Measurements ◽

Working Distance ◽

Beam Currents

The capability to obtain symmetrical images at voltages as low as 200 eV and beam currents less than 9 pico amps is believed to be advantageous for metrology and study of dielectric or biological samples. Symmetrical images should allow more precise and accurate line width measurements than currently achievable by traditional secondary electron detectors. The low voltage and current capability should allow imaging of samples which traditionally have been difficult because of charging or electron beam damage.The detector system consists of a lens mounted dual anode MicroChannel Plate (MCP) detector, vacuum interface, power supplies, and signal conditioning to interface directly to the video card of the SEM. The detector has been miniaturized so that it does not interfere with normal operation of the SEM sample handling and alternate detector operation. Biasing of the detector collection face will either add secondaries to the backscatter signal or reject secondaries yielding only a backscatter image. The dual anode design allows A−B signal processing to provide topological information as well as symmetrical A+B images.Photomicrographs will show some of the system capabilities. Resolution will be documented with gold on carbon. Variation of voltage, beam current, and working distance on dielectric samples such as glass and photoresist will demonstrate effects of common parameter changes.

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What Can We Learn From Factorial Surveys About Human Behavior?

Methodology ◽

10.1027/1614-2241/a000161 ◽

2019 ◽

Vol 15 (1) ◽

pp. 19-30 ◽

Cited By ~ 10

Author(s):

Knut Petzold ◽

Tobias Wolbring

Keyword(s):

Social Sciences ◽

Behavioral Intentions ◽

Actual Behavior ◽

Full Time ◽

Factorial Survey ◽

Survey Experiment ◽

Intended Behavior ◽

The Social ◽

Survey Experiments ◽

High Level

Abstract. Factorial survey experiments are increasingly used in the social sciences to investigate behavioral intentions. The measurement of self-reported behavioral intentions with factorial survey experiments frequently assumes that the determinants of intended behavior affect actual behavior in a similar way. We critically investigate this fundamental assumption using the misdirected email technique. Student participants of a survey were randomly assigned to a field experiment or a survey experiment. The email informs the recipient about the reception of a scholarship with varying stakes (full-time vs. book) and recipient’s names (German vs. Arabic). In the survey experiment, respondents saw an image of the same email. This validation design ensured a high level of correspondence between units, settings, and treatments across both studies. Results reveal that while the frequencies of self-reported intentions and actual behavior deviate, treatments show similar relative effects. Hence, although further research on this topic is needed, this study suggests that determinants of behavior might be inferred from behavioral intentions measured with survey experiments.

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Intrinsic Characteristics of Quasars Redshifts

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v4i3.2020 ◽

2014 ◽

Vol 4 (3) ◽

pp. 655-661

Author(s):

Waleed Elsanhoury

Keyword(s):

Absolute Magnitude ◽

Sloan Digital Sky Survey ◽

Strong Correlations ◽

Sky Survey

Using Sloan Digital Sky Survey SDSS catalog, some intrinsic characteristics of Quasars (10,000 points) are developed of these are the strong correlations between redshifts and other parameters, e.g. combined magnitude, luminosity, and absolute magnitude .Moreover ,the Karlsson peak of our sample is also computed.

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