difficult produce the 60% pulse fraction observed in Kes 79 NS. How, then, did we accomplish this?

In fact, diffuse hot spots of finite size (with varying temperatures), combined with the beaming due to anisotropic photon opacities in magnetic fields, are essential for generating the large pulse fraction in our model. In our calculations, the hottest regions with radii of $\sim 0.5^\circ$ around each magnetic pole do not produce pulse fractions higher than about $40\%$. Instead, it is the subsequent annuli of decreasing effective temperature that create the bulk of the pulsed emission. Therefore, to quantitatively model the light curves of NS surface emission, it is important to go beyond the single-temperature hot spot approximation widely used in many previous studies. It is for this reason that a reasonably efficient method, such as TTFT developed in Section 2, is necessary in order to add up atmosphere emissions from many different patches of the NS surface to produce synthetic light curves.

Crustal Magnetic Field Evolutionary Timescale
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The crustal magnetic field assumed in our model (Section 3) is unlikely to be unique for producing the observed light curve of Kes 79 NS. In a way, it is the most conservative magnetic 