Subaru/FOCAS Optical Spectroscopy for a possible IceCube-170922A counterpart TXS 0506+056
ATel #10890; Tomoki Morokuma (The University of Tokyo), Yasuyuki T. Tanaka (Hiroshima University), Kouji Ohta (Kyoto University), Yoshiki Matsuoka, Takuji Yamashita, Nanako Kato (Ehime University)
on 25 Oct 2017; 04:36 UT
Credential Certification: Tomoki Morokuma (firstname.lastname@example.org)
Subjects: Optical, Neutrinos, Blazar
We performed optical spectroscopic observations on September 30 and October 1, 2017 (UT) with the 8.2-m Subaru telescope and Faint Object Camera and Spectrograph (FOCAS) for TXS 0506+056 which is a possible counterpart to the IceCube-170922A high-energy neutrino event (Tanaka et al. 2017, ATel #10791). The wavelength ranges covered are 4700-8200A (1.34 angstroms per pixel) and 7500-10500A (0.74 angstroms per pixel), and the obtained spectral resolutions are R~400 and 1200, respectively. The signal-to-noise ratios are roughly 100 per pixel. As reported by Steele (2017, ATel #10799), van Soelen et al. (2017, ATel #10830), Coleiro & Chaty (2017, ATel #10840), we do not find any other significant absorption or emission lines than the atmospheric and Galactic lines.