K-derived planetary indices (am, aa, and Kp)

This data set contains the K-derived planetary indices (am, aa, and Kp). The K-derived planetary indices (am, an, as, aa, and Kp) were traditionally computed on a monthly basis with K-indices hand scaled on analogue magnetograms and provided as hard copies by the observatories. Provisional values were thus circulated with a delay of a few weeks after the end of the month of observation. Definitive values were computed once definitive K values made available by all the observatories. Provisional and definitive values are still computed with the K values provided by the observatories. Provisional values are circulated on a monthly basis with a few weeks delay for am, an, and as, twice a month with a few weeks delay for Ap, and on a weekly basis with a few days delay for aa. Recent indices which are not yet validated are provisional Indices and indicated in the data files with a provisional flag.