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Title: ASTRONOMICAL AND PHYSICAL DATA FOR METEOROIDS RECORDED BY THE ALTAIR RADAR

Abstract

No abstract prepared.

Authors:
;
Publication Date:
Research Org.:
Los Alamos National Lab., NM (US)
Sponsoring Org.:
US Department of Energy (US)
OSTI Identifier:
788223
Report Number(s):
LA-UR-01-5646
TRN: US200306%%175
DOE Contract Number:
W-7405-ENG-36
Resource Type:
Conference
Resource Relation:
Conference: Conference title not supplied, Conference location not supplied, Conference dates not supplied; Other Information: PBD: 1 Oct 2001
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; METEOROIDS; RADAR; ASTRONOMY; PHYSICAL PROPERTIES; LANL

Citation Formats

P. G. BROWN, and D. O. REVELLE. ASTRONOMICAL AND PHYSICAL DATA FOR METEOROIDS RECORDED BY THE ALTAIR RADAR. United States: N. p., 2001. Web.
P. G. BROWN, & D. O. REVELLE. ASTRONOMICAL AND PHYSICAL DATA FOR METEOROIDS RECORDED BY THE ALTAIR RADAR. United States.
P. G. BROWN, and D. O. REVELLE. Mon . "ASTRONOMICAL AND PHYSICAL DATA FOR METEOROIDS RECORDED BY THE ALTAIR RADAR". United States. doi:. https://www.osti.gov/servlets/purl/788223.
@article{osti_788223,
title = {ASTRONOMICAL AND PHYSICAL DATA FOR METEOROIDS RECORDED BY THE ALTAIR RADAR},
author = {P. G. BROWN and D. O. REVELLE},
abstractNote = {No abstract prepared.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Oct 01 00:00:00 EDT 2001},
month = {Mon Oct 01 00:00:00 EDT 2001}
}

Conference:
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  • We present preliminary results of orbital and physical measurements of a small selection of meteoroids observed at UHF frequencies by the ALTAIR radar on Kwajalein Island on November 17, 1998. The head echoes observed by ALTAIR allowed precise determination of velocities and decelerations from which orbits and masses of individual meteoroids derived from numerical modelling have been measured. During these observations, the ALTAIR radar detected average head echo rates of 1665 per hour.
  • The report presents preliminary results obtained from data collected with ALTAIR, a high-power VHF/UHF radar, during the Wideband Equatorial Program. The Wideband Equatorial Program is a coordinated field program sponsored by the Defense Nuclear Agency (DNA) to study the physical processes underlying the production of intense field-aligned irregularities and the effects of those irregularities on satellite communication channels that operate in the gigahertz frequency range. This radar is sensitive enough for incoherent-scatter measurements as well as being capable of spatially mapping E and F region irregularities as a function of time. With data collected from the operation of ALTAIR inmore » a sector scan mode it is possible to determine the spatial distribution of 1-m spread-F irregularities and their dynamics, and to relate them to the parameters of the background equatorial ionosphere. These relationships provide a means of critically evaluating proposed source mechanisms of equatorial spread-F.« less
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  • A key online and off-line software component of the Sloan Digital Sky Survey (SDSS) is Shiva. Shiva provides a readily extendible framework upon which the SDSS data reduction pipeline software is built. In this paper we present an introduction to the Shiva data analysis framework. We briefly discuss the features and the inherent prototyping and rapid development capabilities that make Shiva an integral part in the on-going development of SDSS software.
  • ICP emission analyses are prone to errors due to changes in power level, nebulization rate, plasma temperature, and sample matrix. As a result, accurate analyses of complex samples often require frequent bracketing with matrix matched standards. Information needed to track and correct the matrix errors is contained in the emission spectrum. But most commercial software packages use only the analyte line emission to determine concentrations. Changes in plasma temperature and the nebulization rate are reflected by changes in the hydrogen line widths, the oxygen emission, and neutral ion line ratios. Argon and off-line emissions provide a measure to correct themore » power level and the background scattering occurring in the polychromator. The authors` studies indicated that changes in the intensity of the Ar 404.4 nm line readily flag most matrix and plasma condition modifications. Carbon lines can be used to monitor the impact of organics on the analyses and calcium and argon lines can be used to correct for spectral drift and alignment. Spectra of contaminated groundwater and simulated defense waste glasses were obtained using a Thermo Jarrell Ash ICP that has an echelle CID detector system covering the 190-850 nm range. The echelle images were translated to the FITS data format, which astronomers recommend for data storage. Data reduction packages such as those in the ESO-MIDAS/ECHELLE and DAOPHOT programs were tried with limited success. The radial point spread function was evaluated as a possible improved peak intensity measurement instead of the common pixel averaging approach used in the commercial ICP software. Several algorithms were evaluated to align and automatically scale the background and reference spectra. A new data reduction approach that utilizes standard reference images, successive subtractions, and residual analyses has been evaluated to correct for matrix effects.« less