The Spectral Irradiance Monitor: Measurement Equations and Calibration   总被引：2，自引：0，他引：2  

Jerald W. Harder  Juan Fontenla  George Lawrence  Thomas Woods  Gary Rottman 《Solar physics》2005,230(1-2):169-204

The Spectral Irradiance Monitor (SIM) is a satellite-borne spectrometer aboard the Solar Radiation and Climate Experiment (SORCE) that measures solar irradiance between 200 and 2700 nm. This instrument employs a Fèry prism as a dispersing element, an electrical substitution radiometer (ESR) as the primary detector, and four additional photodiode detectors for spectral scanning. Assembling unit level calibrations of critical components and expressing the sensitivity in terms of interrelated measurement equations supplies the instrument's radiant response. The calibration and analysis of the spectrometer's dispersive and transmissive properties, light aperture metrology, and detector characteristics provide the basis for these measurement equations. The values of critical calibration parameters, such as prism and detector response degradation, are re-measured throughout the mission to correct the ground-based calibration.  相似文献   

The 2dF Galaxy Redshift Survey: correlation with the ROSAT-ESO flux-limited X-ray galaxy cluster survey     

Matt Hilton  Chris Collins  Roberto De Propris  Ivan K. Baldry  Carlton M. Baugh  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Shaun Cole  Matthew Colless  Warrick J. Couch  Gavin B. Dalton  Simon P. Driver  George Efstathiou  Richard S. Ellis  Carlos S. Frenk  Karl Glazebrook  Carole A. Jackson  Ofer Lahav  Ian Lewis  Stuart Lumsden  Steve J. Maddox  Darren Madgwick  Peder Norberg  John A. Peacock  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2005,363(2):661-674

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Boltzmann Equilibrium of Endothermic Heavy Nuclear Synthesis in the Universe and a Quark Relation to the Magic Numbers     

Heinrich Hora  George H. Miley  Frederick Osman 《Astrophysics and Space Science》2005,298(1-2):247-253

As laser–plasma interactions access ever-increasing ranges of plasma temperatures and densities, it is interesting to consider whether they will some day shed light on questions concerning nuclear synthesis. One such open question is the process of endothermic nuclear synthesis for elements with A > 60, thought to have taken place at a point in time during the big bang, or currently in supernovae. We present an explanation based on a Boltzmann equilibrium condition, in combination with the change of the Fermi-statistics from the relativistic branch for hadrons from higher than nuclear densities to the lower density subrelativistic branch. The Debye length confinement of nuclei breaks down at the relativistic change, thus leading to the impossibility of nucleation of the quark-gluon state at higher than nuclear densities. Taking the increment for the proton number Z as Z′ = 10 of the measured standard abundance distribution (SAD) of the elements for a Boltzmann probability for heavy element synthesis, a sequence 3 ⁿ was found with the exponent n for the sequence of the magic numbers. The jump between the magic numbers 20 and 28 does not need then the usual spin-orbit explanation.  相似文献   

Characteristics and OSL minimum ages of relict fluvial deposits near Sossus Vlei,Tsauchab River,Namibia, and a regional climate record for the last 30 ka     

George A. Brook  Pradeep Srivastava  Eugene Marais 《第四纪科学杂志》2006,21(4):347-362

The present end‐point of the Tsauchab River is at Sossus Vlei, 30 km into the Namib Sand Sea. Interdune deposits in three depressions west and southwest of the vlei include channel and interdune lithofacies associations but no deposits typical of river end‐points or of groundwater seepage into interdune areas. The two lithofacies associations show that the Tsauchab River extended further into the sand sea in the past. It had a well‐developed channel and a higher flow than today that caused flooding of adjacent interdune areas. OSL 4‐mm aliquot minimum ages indicate that the Tsauchab River reached 2–3 km beyond its present end‐point at ca. 25 ka and ca. 9–7 ka, and that the river was more active from 0.9–0.3 ka. The eastward migration of the river end‐point since ca. 7 ka suggests a reduction in flood magnitude accompanied by the gradual invasion of the Sossus Vlei area by dunes. The regional data indicate an additional wet interval at ca. 15 ka that is so far not recorded in the Sossus area. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

Foreword     

George W. Housner 《地震工程与工程振动(英文版)》2003,2(1):i-i

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Foreword     

George W. Housner 《地震工程与工程振动(英文版)》2005,4(1):i-i

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Results from the AIM-IT Meteor Tracking System     

Peter S. Gural  Peter M. Jenniskens  George Varros 《Earth, Moon, and Planets》2004,95(1-4):541-552

The recent development and data collection results of the Astrobiology Instrumentation for Meteor Imaging and Tracking (AIM-IT) system, has demonstrated an ability to point narrow field-of-view instruments at transient events such as meteors. AIM-IT uses the principle of tracking moving objects via a paired set of relay mirrors along with an integrated hardware/software solution, to acquire and track meteors in real-time. Development of the instrument has progressed from a prototype rocker-box system through more recent use of a fast response mirror system during several meteor shower campaigns. Several narrow field of view instruments have been deployed using AIM-IT including high spatial resolution video, high frame rate video, and meteor spectrographic equipment. Analysis of the imagery shows evidence for meteor fragmentation in as many as 20% of the meteors tracked thus far. The success of the AIM-IT technology in tracking meteors during their luminous flight provides a new tool in enhancing the capabilities and data volume that can be obtained with existing narrow field of view instruments.  相似文献   

The self-regulated winds of long-period variable stars     

Curtis Struck  Daniel C. Smith  Lee Anne Willson  Gary Turner  George H. Bowen 《Monthly notices of the Royal Astronomical Society》2004,353(2):559-570

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Galaxy groups in the 2dFGRS: the group-finding algorithm and the 2PIGG catalogue     

V. R. Eke  Carlton M. Baugh  Shaun Cole  Carlos S. Frenk  Peder Norberg  John A. Peacock  Ivan K. Baldry  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Matthew Colless  Chris Collins  Warrick Couch  Gavin Dalton  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Karl Glazebrook  Carole Jackson  Ofer Lahav  Ian Lewis  Stuart Lumsden  Steve Maddox  Darren Madgwick  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2004,348(3):866-878

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Mid‐infrared study of stones from the Sutter's Mill meteorite     

Michel Nuevo  Scott A. Sandford  George J. Flynn  Susan Wirick 《Meteoritics & planetary science》2014,49(11):2017-2026

The Sutter's Mill meteorite fell in northern California on April 22, 2012. Several fragments of the meteorite were recovered, some of them shortly after the fall, others several days later after a heavy rainstorm. In this work, we analyzed several samples of four fragments―SM2, SM12, SM20, and SM30―from the Sutter's Mill meteorite with two infrared (IR) microscopes operating in the 4000–650 cm^?1 (2.5–15.4 μm) range. Spectra show absorption features associated with minerals such as olivines, phyllosilicates, carbonates, and possibly pyroxenes, as well as organics. Spectra of specific minerals vary from one particle to another within a given stone, and even within a single particle, indicating a nonuniform mineral composition. Infrared features associated with aliphatic CH₂ and CH₃ groups associated with organics are also seen in several spectra. However, the presence of organics in the samples studied is not clear because these features overlap with carbonate overtone bands. Finally, other samples collected within days after the rainstorm show evidence for bacterial terrestrial contamination, which indicates how quickly meteorites can be contaminated on such small scales.  相似文献