Optical spectroscopy of the ZTF19aacomym transient in WISEA J014421.10+500657.0
ATel #13531; I. Zaznobin (IKI), R. Burenin (IKI), M. Eselevich (ISZF SO RAN), S. Sazonov (IKI), M. Pavlinsky (IKI), R. Sunyaev (IKI), on behalf of the Russian SRG/eROSITA Consortium
on 28 Feb 2020; 06:37 UT
Credential Certification: Rodion Burenin (rodion@hea.iki.rssi.ru)
Subjects: Optical, X-ray, AGN, Transient
The long-lived optical transient ZTF19aacomym (ZTF) in the nucleus of galaxy WISEA J014421.10+500657.0, from which a significant X-ray flux has been detected by SRG/eROSITA (I. Khabibullin et al., ATel #13529), was observed on Feb 21 2020 at 12:00-13:00 UT and on Feb 27 2020 at 15:00-16:00 UT with the Sayan observatory's AZT-33IK 1.6-m telescope, using the ADAM low and medium resolution spectrograph. The slit was positioned to obtain the spectrum of the galaxy's nucleus. Note that supernova SN 2019vzf was outside of the slit.
The low resolution spectrum of the galaxy's nucleus shows a flat continuum with broad Halpha and Hbeta lines of ~4500km/s width and narrow Halpha and [NII],6583 lines (~500km/s). In the combined spectrum, there is an indication on the presence of a weak [OIII],5007 line with an equivalent width of ~2 angstrom. The narrow lines are observed at redshift z=0.0625.
The equivalent width of the Hbeta line is ~21 angstrom, and more detailed modeling is needed to accurately estimate the equivalent width of the broad Halpha line due to the presence of narrow Halpha and [NII] lines as well as atmospheric absorption lines. The luminosity in the Hbeta line is ~5^40 erg/s. There is no change in the line widths or equivalent widths between the two observations, within the uncertainties.
