A systematic search for changing-look quasars in SDSS
نویسندگان
چکیده
منابع مشابه
A search for changing-look AGN in the Grossan catalog
We observed with XMM-Newton 4 objects selected from the Grossan (1992) 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 13218+0552 and NGC 1667. None of the sources was caught in a high flux state during the XMM-Newton observatio...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2016
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/stv2997