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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 is a space complex of telescopes that works at the Earth orbit from August 2001 and includes the following instruments …
SPIRIT data types
4 channels
TELESCOPE 2 2 channels
TELESCOPE 1 4 channels
IMAGING SPECTROGELIOGRAPH Mg XII 8.42 A 2 channels
XUV SPECTROGELIOGRAPH2 channels
TELESCOPE 1171 A channel195 A channel284 A channel304 A channel
TOTAL: ~ 14 000 images during 4.5 years (12 Gb)
TELESCOPE 2175 A channel304 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 SPECTROGELIOGRAPH177-207 A285-335 A
TOTAL: ~ 9 000 images during 4.5 years (10 Gb)
TOTAL NUMBER OF THE SPIRIT IMAGESTOTAL NUMBER OF THE SPIRIT IMAGES
TELESCOPE 1
171 A 2 800 195 A 4 500
284 A 3 500 304 A 3 100
TELESCOPE 2
175 A 40 500 304 A 40 500
IMAGING SPECTROGELIOGRAPH Mg XII
Mg 1 87 500 Mg 2 104 000
XUV SPECTROGELIOGRAPH
XUV 190 3 400 XUV 304 5 000
TOTAL: 295 000 images of the Sun during 4.5 years of work
Full cycle of SPIRIT data processing1. On-board registration and processing
2. Data analysis and improvement
3. Converting data to FITS and filling the database
On-board processing
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
Methods of the lost pixel reconstruction:a) Comparison with the
same pixels in the adjacent images
b) bilinear interpolation from the adjacent rows
Lost data recovering
Method of the reconstruction (3 steps):1. We synthesize the mask of
damage (one mask for one SPIRIT channel)
2. 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
Recovering of the places with filter damage
Methods of the mask calculationa) Averaging of the long series of one channel images
b) Method of Kuhn-Lin-Loranz (PASP, 1991, V. 103, P. 1097)
Flat field mask
Flat field correction
F1 F20F3F2
…
FaaBackgroundi
i
20
10
Background subtraction
Background subtraction
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=253.5Y=301.2R=182.5Итерация 1Итерация 2Итерация 3
Orientation problem and its solving
An example of SPIRIT data after the finishing of full processing cycle
Converting the data to FITS format
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.
Header of the SPIRIT fits files consists of the two main parts
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
SPIRIT HEADER SOHO/EIT HEADER
coincides with the SOHO/EIT
Lower part of the header(provides additional information on the SPIRIT data)
Ballistic information
Structure of the SPIRIT data base
SQL Database Management System
HTMLSPIRIT home page
FTP base of images
Direct FTP access
Accessthrough web site
Request
Request
SPIRIT FTP server
Address: ftp://serv99.lebedev.ru/dataLogin: xrasuserPassword: userxras
Now are acceptable through FTP:• Telescope 1
4 channels, all the images, free access
• Telescope 22 channels, all the images, free access
• XUV-Spectrogeliograph2 channels, all the images, free access
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
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