![]() ![]() ![]() ![]() We are currently working on a semi-automatic pipeline for calibrating the visibility data. If you are interested the Practical Calibration Tutorial describes the procedure. Calibration: Calibrating EOVSA data is an involved process.Name convention is YYYYMMDD/IDBYYYYMMDDHHMMSS, where the time in the file name indicates the start time of the visibility data. Each data file is usually 10 minutes in duration. Once you identify the flare time, you can find the full-resolution (1-s cadence) uncalibrated visibility files (in Miriad format) at this link. We are currently working on a pipeline to create quicklook full-disk images for implementation at the RHESSI Browser in a way similar as the RHESSI quicklook images. More information can be found on this page. Flare times can be easily seen in the EOVSA dynamic spectra, which usually appear as vertical bright features across many frequency bands. The effects of spatial information blended in the cross-power visibilities can be clearly seen as the "U"-shaped features throughout the day, which are due to the movement of the Sun across the sky that effectively changes the length and orientation of the baselines. The overview EOVSA dynamic spectra are from the median of the uncalibrated cross-power visibilities at a few short baselines, which are not (but a good proxy of) the total-power dynamic spectra. An example of the overview EOVSA dynamic spectrum for 2017 Aug 21 is shown in the figure on the right. Also note that EOVSA data were not commissioned for spectroscopic imaging prior to April 2017. Note if a time is selected at early UTC hours (e.g., 0-3 UT), it will show the EOVSA dynamic spectrum from the previous day. Then select year/month/date to view the overall EOVSA dynamic spectrum. First, check the "EOVSA Radio Data" box on the data selection area (top-left corner). Currently the most convenient way for browsing EOVSA data is through the RHESSI Browser. ![]()
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