XPS Version 10 (8 December 2009):
The main changes for SORCE XPS Version 10 Level 4 data products are an algorithm change to more properly handle GOES X-ray data and an update for the CHIANTI model parameters. Both changes were needed to properly process the GOES and XPS data during solar cycle minimum conditions. The previous XPS processing used two CHIANTI model spectra as 50% Quiet Sun and 50% Coronal Hole components to describe the solar cycle XUV irradiance during cycle minimum. Now that we have XPS cycle minimum data, the new fit to XPS data indicates that CHIANTI model contributions are 32% Quiet Sun and 68% Coronal Hole components are needed for this current cycle minimum. The changes in the SORCE XPS Version 10 data are most obvious from late 2006 to the present (2009).
XPS Version 9 (12 December 2008):
- Improved dark corrections for post anomaly science products.
XPS Version 8 (14 February 2007):
- Provides data for post filter wheel anomaly that occurred on day 353 of year 2005. Data processing code has been modified to correctly determine diode dark vales from pre and post solar observations and to allow monthly calibration of each primary diode. Processing data prior to the anomaly remains unchanged.
- For those needing higher spectral resolution, Version 8 now contains an XPS Level 4 data product that has the solar spectrum in the 0-40 nm range in 0.1 nm intervals, whereby the Level 4 product spectra are based on the CHIANTI spectral model scaled to match the XPS photometer currents (signals).