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tokens: the FD energy scale (determined calorimetrically; Abu-Zayyad et al. 2013b ; Tsunesada et al. 2017 ). The systematic uncertainty on the TA energy scale is 21% (Abbasi et al. 2016 ) and its energy and angular resolutions are 15%–20% and 10–15, respectively, depending on the event geometry and energy (Abbasi et al. 2014 ). In this Letter we use data collected by the TA SD array in a 9 yr period from 2008 May to 2017 May with reconstructed energies above 43 EeV, zenith angles less than 55°, and declinations δ > −10° using the same quality cuts as in Abbasi et al. ( 2014 ). This data set comprises 284 events. We neglect the finite angular and energy resolution of TA events, and consider the detector fully efficient, i.e. with a flat response for all showers with energies and zenith angles in the considered range, so that its directional exposure ω TA equals the geometrical one for δ > −10°, which varies with declination but not with right ascension (Sommers 2001 ):where φ TA = +393 is the detector latitude and θ m = 55° is the maximum zenith angle accepted. The energy threshold of E min = 43 EeV used in this analysis corresponds to the Auger energy threshold of 39 EeV, at which the most significant correlation with SBG was found. Here we took into account the 10.4% difference between the energy scales of the two experiments as estimated by a comparison of energy spectra around 5 EeV (Verzi et al. 2017 ; Abu-Zayyad et al. 2018 ). 2.2. Source Catalog Following the Auger analysis (Aab et al. 2018 ), we select the candidate sources from a sample of 63 SBGs outside the Local Group compiled by the Fermi -Large Area Telescope (LAT) Collaboration (Ackermann et al. 2012 ) for the gamma-ray emission search. 36 36 Only four of those objects were actually successfully detected in gamma-rays in that work: NGC 253, M82, NGC 4945, and NGC 1068. Imposing the cut of flux greater than 0.3 Jy at 1.4 GHz leaves 23 objects in the catalog of candidate sources. Their UHECR fluxes were assumed to be proportional to their radio fluxes at 1.4 GHz. These objects are listed in Table 1 . Table 1 Selected Source Candidates from the SBG Catalog used in this Analysis (the same as in Aab et al. 2018 ) Note. The last column shows the relative source contribution weighted with the TA directional exposure ω TA . In the Auger analysis, the effect of energy losses by UHECRs during their propagation was found to be negligible in the SBG model, as most of the anisotropic flux originates from sources within a few Mpc; in this Letter, we neglected the losses for simplicity. 2.3. Test Statistic and Flux Model Let be the unit vector representing a direction in the sky, pointing away from the observer. Given two flux models describing a null hypothesis and an alternative hypothesis, respectively, and the directional exposure of an experiment, the test statistic (hereinafter ) is defined as twice the log-likelihood ratioand being the reconstructed arrival direction of the i -th observed