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SPIRIT – database and data access. Andrey A. Perzov, Sergey V. Kuzin, Sergey A. Bogachev, Vladimir A. Slemzin, Sergey V. Shestov, Oleg I. Bugaenko. SPIRIT data types.
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SPIRIT – database and data access Andrey A. Perzov, Sergey V. Kuzin, Sergey A. Bogachev, Vladimir A. Slemzin, Sergey V. Shestov, Oleg I. Bugaenko
SPIRIT data types SPIRIT is a space complex of telescopes that works at the Earth orbit from August 2001 and includes the following instruments … 4 channels
TELESCOPE 2 2 channels TELESCOPE 1 4 channels IMAGING SPECTROGELIOGRAPH Mg XII 8.42 A 2 channels XUV SPECTROGELIOGRAPH 2 channels
TELESCOPE 1 171 A channel 195 A channel 284 A channel 304 A channel TOTAL: ~ 14 000 images during 4.5 years (12 Gb)
TELESCOPE 2 175 A channel 304 A channel TOTAL: ~ 81 000 images during 4.5 years (50 Gb)
IMAGING SPECTROGELIOGRAPH Mg XII 8.42 A TOTAL: ~ 191 000 images during 4.5 years (200 Gb)
XUV SPECTROGELIOGRAPH 177-207 A 285-335 A TOTAL: ~ 9 000 images during 4.5 years (10 Gb)
Full cycle of SPIRIT data processing 1. On-board registration and processing 3. Converting data to FITS and filling the database 2. Data analysis and improvement
Data analysis and improvement Automatic software: • Lost data filling • Flat field correction User software: • Background subtraction • Finding of coordinates Full package of SPIRIT software will be available in SSW from January-February 2006
Lost data recovering Methods of the lost pixel reconstruction: • Comparison with the same pixels in the adjacent images • bilinear interpolation from the adjacent rows
Recovering of the places with filter damage Method of the reconstruction (3 steps): • We synthesize the mask of damage (one mask for one SPIRIT channel) • We multiply the data matrix by this mask of damage 3. Places of most strong damage are reconstructed by the bilinear interpolation as the lost pixels
Flat field correction Flat field mask Methods of the mask calculation a) Averaging of the long series of one channel images b) Method of Kuhn-Lin-Loranz (PASP, 1991, V. 103, P. 1097)
Background subtraction F1 F2 F3 F20 …
Orientation problem and its solving Description of the problem • Axe of the satellite varies slowly in time that leads to some uncertainty in the position of the Sun disk in the image • For correct analysis of the data, it is necessary to compensate this shifting with the precision of about 1 pixel
Orientation problem and its solving Method We find the position of the Sun disk in the image with our own method based on the successive approaches to the Sun limb Result (in CCD pixels) X=253.5 Y=301.2 R=182.5 Итерация 1 Итерация 2 Итерация 3
An example of SPIRIT data after the finishing of full processing cycle
Converting the data to FITS format Header of the SPIRIT fits files consists of the two main parts The upper part coincides with the SOHO/EIT header. It allows to directly apply all the EIT programs for processing of the SPIRIT fits files. The lower part includes an additional information on the SPIRIT data. This information is necessary for more detail processing – for example, for decision of ballistic tasks.
Upper part of the header coincides with the SOHO/EIT SPIRIT HEADER SOHO/EIT HEADER
Lower part of the header(provides additional information on the SPIRIT data) Ballistic information
Structure of the SPIRIT data base SQL Database Management System Request HTML SPIRIT home page Access through web site Request FTP base of images Direct FTP access
SPIRIT FTP server • Address: ftp://serv99.lebedev.ru/data • Login: xrasuser • Password: userxras • Now are acceptable through FTP: • Telescope 1 • 4 channels, all the images, free access • Telescope 2 • 2 channels, all the images, free access • XUV-Spectrogeliograph • 2 channels, all the images, free access
SPIRIT web page Address: http://spirit.xras.lebedev.ru/
FTP access through web page Address: http://spirit.xras.lebedev.ru/data-access-ftp.html
Access through SQL based data search system Address: http://spirit.xras.lebedev.ru/data-access.php