ACE SWEPAM/SWICS Level 3 Merged Solar Wind Proton Data

The data are typically from the SWEPAM instrument. But because SWEPAM has reduced sensitivity at the lowest energies, and at times underestimates the proton density, especially for very slow wind, proton density is sometimes culled from low-speed (.LT. ~350 km/s) intervals in the SWEPAM Level 2 data, and proton temperature may also be culled.

More rarely, the solar wind velocity may also be culled, especially during periods of both high solar energetic particle background and high wind speeds. In these cases, SWICS-determined proton density and temperature, and possibly also flow speed (not velocity vectors), are included in the data records, with a flag to indicate whether, and which, SWICS parameters are in the records. As of July, 2012, data were available to the end of 2009.