Available Data Products

SSOC makes data available from the following instruments located at DST:

  • IBIS dual-beam spectroscopic with 854.2 nm, 656.3 nm, and 589.6 nm spectral lines.
  • ROSA image data in 350 nm, 417 nm, G-band, and Ca-K bands.
  • Zyla Hydrogen-alpha (656.3 nm) imager.
  • FIRS 1083.0 nm spectro-polarimetric data.
  • FIRS slitjaw imager.
  • SPINOR Sarnoff spectro-polarimetric with 854.2 nm and 587.6 nm lines.
  • SPINOR Flir spectro-polarimetric with the 630.2 nm lines.
  • SPINOR slitjaw imager.
  • HAZEL spectro-polarimetric inversions from FIRS 1083.0 nm data.
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    The above data products are available in three different levels:

  • Level 0 raw, unprocessed data (images) straight from DST. These data are not science-ready, but some customers prefer to download this kind of data to do the processing/calibration themselves.
  • Level 1 processed from the Level 0 data. Level 1 means effects from the telescope and instrument optics have been removed from the raw data through the use of a flat-field correction. For some instrument data sets, atmospheric distortions have been removed, too i.e. ROSA, Zyla, and IBIS. Level 1 products are considered science-ready and are ready to be used by SSOC customers.
  • Level 2 processed from the Level 1 data. Level 2 means physical variables, such as temperature, pressure, magnetic field, etc. have been deduced from the Level 1 data through the use of a physical model or similar. At the time of writing, the HAZEL inversions are the only Level 2 product that SSOC offers to its customers.
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    Arrangement of Data Within the Repository

    Observing days are organized within the repository using the following directory structure:

    repository-root-directory/YYYY/MM/DD/

    YYYY is the four-digit year during which the observation was taken. MM is the two-digit month during which the observation was taken (1-12). DD is the two-digit day-of-month the observation was taken (1-31).

    Level 0 Products

    Level 0 data are arranged similarly, but with some extra directories to organize the instrument data sets:

    repository-root-directory/YYYY/MM/DD/level0/DDmmmYYYY_<instrument-name>/

    mmm is the three-letter abbreviated month e.g. jan, feb, mar, apr, jun, etc.. Instrument-name will take the following values:

  • 3500 - ROSA 350.0 nm image data.
  • 4170 - ROSA 417.0 nm image data.
  • cak - ROSA Calcium II K image data.
  • firs - FIRS 1080.3 nm spectro-polarimetric data.
  • firs_slitjaw - FIRS slitjaw image data.
  • gband - ROSA G-band image data.
  • ibis - IBIS narrowband spectral-imaging data.
  • spinor_flir_6302 - SPINOR 630.2nm spectro-polarimetric data.
  • spinor_sarnoff_5876 - SPINOR 587.6nm spectro-polarimetric data.
  • spinor_sarnoff_8542 - SPINOR 854.2nm spectro-polarimetric data.
  • spinor_slitjaw - SPINOR slitjaw image data.
  • whitelight - IBIS broadband image data.
  • zyla - Zyla hydrogen-alpha image data.
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    Level 1 Products

    Level 1 data are arranged similarly yet:

    repository-root-directory/YYYY/MM/DD/level1/<instrument-name>/

    Instrument-name is a little more straightforward for the Level 1 data, and can take the following values:

  • firs - FIRS 1083.0 nm data.
  • ibis - IBIS data.
  • rosa - ROSA data.
  • spinor/xxxx - SPINOR data where xxxx is a four-digit wavelength in angstroms.
  • zyla - Zyla data. The timestamps were reconstructed during the data reduction and may not be accurate.
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    Note that the slitjaw imagers for FIRS and SPINOR are not present. SSOC does not currently possess software to calibrate FIRS or SPINOR slitjaw image data.

    Level 1 ROSA and Zyla Products

    ROSA Level 1 data directories are further split into four sub directories because of the four imagers onboard that instrument. Within the level1 directory for a given observing day, those directories are:

  • .../rosa/3500/ - ROSA 350.0 nm image data.
  • .../rosa/4170/ - ROSA 417.0 nm image data.
  • .../rosa/cak/ - ROSA Calcium K image data.
  • .../rosa/gband/ - ROSA G-band image data.

    • Within each of those directories may be three additional directories: .../preSpeckle, .../speckle, and .../postSpeckle which contain the data needed for speckle analysis with KISIP, the speckle-analyzed data, and the speckle-analyzed data written in FITS format, respectively. The .../postSpeckle directory contains the final Level 1 ROSA products that users will want to download.

    Level 1 IBIS Products

    IBIS Level 1 data directories are further split into directories named based on the start time of each observation in UT e.g. .../level1/ibis/HHMMSS/. IBIS instrument was retired in June 2019.

    Observer Logs

    The observer logs contain written information from the telescope observers. The information tells the data scientist what was being observed e.g. a filament or sunspot, which instruments were in use, where the telescope was pointed on the solar disk, and whether or not there were any problems with the instruments while observations were underway. Logs also contain important messages from the instrument control hardware.The logs are stored using the following directory convention:

    repository-root-directory/YYYY/MM/DD/DDmmmYYYY_observer_logs/

    YYYY, MM, DD, and mmm are described in the preceding section.