Fig. 12.
Optical spectra of TXS 0506+056 taken with Nayuta/MALLS (red), Kanata/HOWPol (blue), Gemini-South/GMOS (green), and Subaru/FOCAS (black). The Subaru/FOCAS spectra are the same as those shown in IceCube Collaboration (2018). There are no changes in spectral features. Noisy wavelength ranges are omitted. The spiky features seen in the spectra are all atmospheric. (Color online)