Software tool for automatic detection of solar plages in the Coimbra Observatory spectroheliograms

T. Barata, S. Carvalho, I. Dorotovic +4

Full-disk spectroheliograms have been taken in Coimbra on a daily basis since 1926 in the Ca II K-line (K1 and K3). Later, in 1989, with the upgrade of the equipment it was possibl…