Analysis of optical Fe II emission with the X-ray properties of a selected sample of I Zw 1 type objects

We report the analysis of medium resolution optical spectra of I Zwicky 1 type objects observed with the 1.9 m telescope at South African Astronomical Observatory (SAAO) at Sutherland. Fourteen bright objects were observed in the southern hemisphere during at least two epochs in the two year period from December 2016 to December 2018. We present our analysis of changes in line strength and profile of three objects, Mkn 1044, 1H 0707–495, and IRAS 03450+0055. Spectra of high signal-to-noise ratio are achieved by combining between 4 and 10 spectra for each epoch. This enables us to decompose and identify the weak individual lines of Fe II and other emissions. To confirm the nature and extent of spectral changes, we compare these combined spectra between the epochs. Mkn 1044 and IRAS 03450+0055 show extended [O III]5007 blue wings with a line width of around 1000 km/s. Both [O III] blue wing and Hβ ILR components match the Fe II profiles, suggesting that they all originate in the same region. No dramatic flux variations are found in Hβ (<10%), Fe II bands (<18%, with the majority of Fe II bands varying less than 4%), and in X-rays (<34% for 1H 0707–495, and <60% for Mkn 1044 between adjacent epochs). The minimum variability found in Fe II lines may imply that the origin of Fe II lines is far from the accretion disk.