A search for changing-look AGN in the Grossan catalog
A search for changing-look AGN in the Grossan catalog
We observed with XMM-Newton 4 objects selected from the Grossan (1992, Ph.D. Thesis) catalog, with the aim to search for new "changing-look" AGN. The sample includes all the sources which showed in subsequent observations a flux much lower than the one measured with HEAO A-1: NGC 7674, NGC 4968, IRAS …