Japanese VLBI Network observation of NVSS J151100+054916 near new gamma-ray source found in the positional error of high-energy neutrino event IceCube-191119A
ATel #13369; K. Niinuma (Yamaguchi U.), Y. Yonekura (Ibaraki U.), K. Motogi, K. Fujisawa (Yamaguchi U.), K. Ohta (Kyoto U.), and K. Kawabata (Hiroshima U.)
on 24 Dec 2019; 14:20 UT
Credential Certification: Kotaro Niinuma (niinuma@yamaguchi-u.ac.jp)
Subjects: Radio, Gamma Ray, Neutrinos, AGN, Blazar
A 6.7 GHz very long baseline interferometry (VLBI) observation of the blazar candidate NVSS J151100+054916 (D'Abrusco et al. 2019, ApJ, 242, 1), which is located 1.6 arcmin away from the best-fit position of new gamma-ray source Fermi J1511+0550 (Garrappa et al. 2019, ATel #13306), positionally consistent with the high energy neutrino event IceCube-191119A (Blaufuss et al. 2019, GCN #26258) was carried out at UT 4h on 2019 Nov 27.
The observation was performed with a one-baseline interferometer consisting of Yamaguchi 32 m and Hitachi 32 m radio telescopes (baseline length ~ 873 km) in the Japanese VLBI Network.
We succeeded to detect NVSS J151100+054916 with a signal-to-noise ratio of 6.3 in 10-min integration at a bandwidth of 512 MHz. Two bright quasars PKS 1510-089 and 1509+022 were also observed to determine the VLBI flux density of NVSS J151100+054916. Its VLBI flux density was 5+/-2 mJy. No significant flare up in the flux density could be found between previous interferometric observations at 1.4 GHz (the flux densities of 6.6+/-0.5 mJy and 6.48+/-0.15 mJy reported in Condon et al. 1998, AJ, 115, 1693, and Helfand et al. 2015, ApJ, 801, 26, respectively) and our VLBI observation at 6.7 GHz at a week after the high energy neutrino event.