IceCube neutrinos-CAZ blazar light curves assoc.

In this paper we utilize the same principle while substantially increasing the number of blazars. We search for the spatio-temporal correlation of 356 IceCube high-energy neutrinos with major optical flares of 3225 radio- and 3814 gamma-ray-selected blazars. We find that, despite the increase in data size, the number of likely spatio-temporal associations remains low and the overall correlation strengths weak.

Two individual associations drive our strongest and the only >2{sigma} post-trial spatio-temporal correlation, occurring with the BL Lac objects of the radio-selected blazar sample. We estimate that <~8% of the detected cosmic neutrinos were emitted by blazars during major optical flares. As a complementary analysis, we compare the synchrotron peak frequency, redshift, Doppler factor, X-ray brightness, and optical variability of spatially neutrino-associated blazars to those of the general blazar population.

We find that spatially neutrino-associated blazars of the tested samples have higher than average Doppler factor and X-ray brightness.