Performance of SAGECal calibration

In this paper, we investigate the accuracy of SAGECal calibration using real models of the sky for the North Celestial Pole (NCP) and 3C196 windows, and compare the results between these two sky models in order to determine a suitable sky window for Epoch of Reionization (EoR) signal detection. The 3C196 window has a bright source at the phase center and many weak sources around it. The NCP window does not have such a bright source, but have only weak sources. The accuracy for estimation of foreground effect for the case of 3C196 is better than that of NCP due to its high signal to noise ratio. On the other hand, residuals after removal of foreground in the real space for 3C196 are higher due to its brightness. According to these results, we conclude that NCP sky window can provide more accurate removal of foregrounds, and 3C196 sky window can provide more accurate estimation of sky noise effect which includes ionospheric and beam effects.

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