Calibration and alignment of metrology system for the Nuclear Spectroscopic Telescope Array mission

A metrology system to measure the on-orbit movement of a ten meter mast has been built for the Nuclear Spectroscopic Telescope Array (NuSTAR) x-ray observatory. In this paper, the metrology system is described, and the performance is measured. The laser beam stability is discussed in detail. Pre-launch alignment and calibration are also described. The invisible infrared laser beams must be aligned to their corresponding detectors without deploying the telescope in Earth’s gravity. Finally, a possible method for in-flight calibration of the metrology system is described

Global Soil Moisture Patterns Observed by Space Borne Microwave Radiometers and Scatterometers

Within the scope of the upcoming launch of a new water related satellite mission (SMOS) a global evaluation study was performed on two available global soil moisture products. ERS scatterometer surface wetness data was compared to AMSR-E soil moisture data. This study pointed out a strong similarity between both products in sparse to moderate vegetated regions with an average correlation coefficient of 0.83. Low correlations were found in densely vegetated areas and deserts. The low values in the vegetated regions can be explained by the limited soil moisture retrieval capabilities over dense vegetation covers. Soil emission is attenuated by the canopy and tends to saturate the microwave signal with increasing vegetation density, resulting in a decreased sensor sensitivity to soil moisture variations. It is expected that the new low frequency satellite mission (SMOS) will obtain soil moisture products with a higher quality in these regions. The low correlations in the desert regions are likely due to volume scattering or to the dielectric dynamics within the soil. The volume scattering in dry soils causes a higher backscatter under very dry conditions than under conditions when the sub-surface soil layers are somewhat wet. In addition, at low moisture levels the dielectric constant has a reduced sensitivity in response to changes in the soil moisture content. At a global scale the spatial correspondence of both products is high and both products clearly distinguish similar regions with high seasonal and inter annual variations. Based on the global analyses we concluded that the quality of both products was comparable and in the sparse to moderate vegetated regions both products may be beneficial for large scale validation of SMOS soil moisture. Some limitations of the studied products are different, pointing to significant potential for combining both products into one superior soil moisture data set. © The Author(s) 2008

London Stage Database

Recovered files, and documents and archival data used to revitalize the London Stage Information Bank, which was completed in the 1970s but had become technologically obsolete. Contents:--Greene_2018_SITAR_3.5in_floppy: Files with this prepending them are program files for the SITAR word processing program, retrieved by Mattie Burkert in 2018 from a 3.5-inch floppy disk sent to her via mail by John Greene, who received it from Ben Schneider in or around 1990.--Greene_2018_SITAR_5.5in_floppy: Files with this prepending them are program files for the SITAR word processing program, retrieved by Mattie Burkert in 2018 from a 3.5-inch floppy disk sent to her via mail by John Greene, who received it from Ben Schneider in or around 1990.--LawrenceU_2014_LSP_data_1990: Files with this prepending themare files retrieved by Mattie Burkert on 15 September 2014 from fourteen 3.5 floppy disks held in the archives of Lawrence University in Appleton, WI, as well as modified version of README file uploaded with these files in 2015 to Minds@UW, the institutional repository of the University of Wisconsin-Madison. Data file extensions are .NPK and .LSP, but they can be opened using a plain text editor.--LawrenceU_2015_Disk_Images_LSP_data_1990: Files with this prepending them are files that come from disk images of fourteen 3.5 floppy disks containing LSP-data files, created by Lawrence University archivist Erin Dix in July 2015 using Guymager and transmitted to Mattie Burkert using Dropbox.--LawrenceU_2016_Programs_Disk_Image_London: Files with this prepending them are files extracted from disk image retrieved by Lawrence University Archivist Erin Dix and transmitted to Mattie Burkert on 17 March 2016 (see files LawrenceU_2016_LSP_KEAmacros.info and LawrenceU_2016_LSP_KEAmacros.000, below). Extraction performed by Dorothea Salo at the University of Wisconsin-Madison on or around 23 March 23 2016 using BitCurator. --Daland_2015_Code_Scans_Combined_Compressed.pdf: Code base, written in PL/1 with limited character set for the London Stage Information Bank project by Will Daland. This code was not preserved in ASCII or EBCDIC text files, but was saved by Will Daland in printed form. From March to August 2015, Will scanned his hard copies as electronic image files using an HP 4620 printer/scanner. The scans here represent code pages 22-97 and 100-121 of the printed code base; the remaining pages were not deemed useful or relevant by Will for recovering the software. Color and brightness settings vary because Will Daland and Mattie Burkert were attempting to identify the best combination for Optical Character Recognition. Pages were transmitted by Daland, page by page, over email to Mattie Burkert in 2015 as individual TIF and PDF files. They were subsequently combined into a single PDF by Mattie Burkert and compressed to meet GitHub file size limitations. Original scan files available from Burkert on request.--Daland_2015_Documentation_Scans_Combined_Compressed_1of3.pdf: Pages 1-23 of documentation for the London Stage Information Bank project by Will Daland. Transmitted by Daland, page by page, over email to Mattie Burkert in 2015 as individual PDF files. Combined into a single PDF by Mattie Burkert, compressed, and split into three separate PDFs to meet GitHub file size limitations. Original scan files available from Burkert on request.--Daland_2015_Documentation_Scans_Combined_Compressed_2of3.pdf: Pages 24-37 of documentation for the London Stage Information Bank project by Will Daland. Transmitted by Daland, page by page, over email to Mattie Burkert in 2015 as individual PDF files. Combined into a single PDF by Mattie Burkert, compressed, and split into three separate PDFs to meet GitHub file size limitations. Original scan files available from Burkert on request.--Daland_2015_Documentation_Scans_Combined_Compressed_3of3.pdf: Pages 38-48 and p.54 of documentation for the London Stage Information Bank project by Will Daland. Transmitted by Daland, page by page, over email to Mattie Burkert in 2015 as individual PDF files. Combined into a single PDF by Mattie Burkert, compressed, and split into three separate PDFs to meet GitHub file size limitations. Original scan files available from Burkert on request.--Greene_2018_Documentation_LSP_SITAR_1990.pdf: Documentation for LSP data and the SITAR word processing program, retrieved by Mattie Burkert in 2018 from a 3.5-inch floppy disk sent to her via mail by John Greene, who recieved it from Ben Schneider in or around 1990.--LawrenceU_2014_Advisory Board_1971.pdf: Agenda of and correspondence related to spring 1971 meeting of London Stage Information Bank Advisory Board, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Correspondence_1973-1980.pdf: Miscellaneous correspondence from the London Stage Information Bank project, 1973-1980, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Diagram_c1973.pdf: Hand-drawn diagram of project workflow for the London Stage Information Bank, circa 1973, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Funding_ACLS_1970.pdf: Correspondence related to the London Stage Information Bank project\u27s funding from the American Council of Learned Societies, 1970, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Funding_NEH_1970.pdf: Correspondence related to the London Stage Information Bank project\u27s funding from the U.S. National Endowment for the Humanities, 1970, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Funding_NSF_1972.pdf: Correspondence related to the London Stage Information Bank project\u27s funding from the U.S. National Science Foundation, 1972, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Lawrentian_1971.pdf: Volume 90, No. 24 of The Lawrentian (30 April 1971), containing a write-up of the London Stage Information Bank project, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Newsletter_1971-1978.pdf: Seven issues of newsletter sent from 1971 to 1978 to parties interested in the London Stage Information Bank, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Photos.pdf: Photos of the London Stage Information Bank team, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Publishing_Agreements_1970-1974.pdf: Publishing agreements between the London Stage Information Bank project, Southern Illinois University Press, and the Society for Theatre Research, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Press_Clippings.pdf: Miscellaneous press clippings related to the London Stage Information Bank project, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Schneider_CV_c1980.pdf: Curriculum Vitae of Professor Ben R. Schneider Jr., including a list of London Stage Information Bank-related publications, circa 1980, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2014_Typist_Instructions_1971.pdf: Instructions for Hong Kong Data Systems typists transcribing marked-up copies of The London Stage 1660-1800 for use on the London Stage Information Bank project, 1971, retrieved by Mattie Burkert on 15 September 2014 from the Lawrence University Archives.--LawrenceU_2016_Documentation_LSP_SITAR_SORTSIT_1996.pdf: Additional documentation for LSP data files, SITAR word processing program, and sorting program SORTSIT, retrieved by Lawrence University Archivist Erin Dix in March 2016 and transmitted to Mattie Burkert using email.--LawrenceU_2016_KEA_Manual_1993.jpg: miscellaneous notes written inside a KEAterm User\u27s Guide, believed to be related to London Stage Information Bank software, retrieved by Lawrence University Archivist Erin Dix in March 2016 and transmitted to Mattie Burkert using email.--LawrenceU_2016_LSP_KEAmacros.000: disk image of floppy disk labeled London Stage Pgms, KEA macros for handling British Library Files .KTM, retrieved by Lawrence University Archivist Erin Dix in March 2016 and transmitted to Mattie Burkert using email.--LawrenceU_2016_LSP_KEAmacros.info: disk image of floppy disk labeled London Stage Pgms, KEA macros for handling British Library Files .KTM, retrieved by Lawrence University Archivist Erin Dix in March 2016 and transmitted to Mattie Burkert using email.--LawrenceU_2016_Schneider_email_1997.pdf: Image of printed email with subject “bib capture macro” found inside KEAterm User\u27s Guide, retrieved by Lawrence University Archivist Erin Dix in March 2016 and transmitted to Mattie Burkert using email

Design, Qualification, Calibration and Alignment of Position Sensing Detector for the NuSTAR Space Mission

A commercial position sensing detector (PSD) has been used to measure mast deflections on a space based X-ray telescope (NuSTAR). This paper describes the space qualification process for utilizing a commercial PSD sensor in space. This discussion includes packaging, environmental testing, selection of flight candidate devices, calibration and alignment

Evaluation of leaf water status by means of permittivity at terahertz frequencies

We present an electromagnetic model of plant leaves which describes their permittivity at terahertz frequencies. The complex permittivity is investigated as a function of the water content of the leaf. Our measurements on coffee leaves (Coffea arabica L.) demonstrate that the dielectric material parameters can be employed to determine the leaf water status and, therefore, to monitor drought stress in plant leaves. The electromagnetic model consists of an effective medium theory, which is implemented by a third order extension of the Landau, Lifshitz, Looyenga model. The influence of scattering becomes important at higher frequencies and is modeled by a Rayleigh roughness factor