Exact cooking time depends on the geometry of the chicken. The inner breast takes longest to cook, and it will continue to get hotter while the chicken is resting because of the thermal mass of the rest of the chicken. The makers of Thermopen have an excellent data-driven analysis.
According to the USDA, in order to achieve a relative reduction in salmonella content of 7.0 log10, i.e. to kill 99.99999% of the bacteria, you should
reach an internal temperature of 78°C
or, alternatively,
maintain (78-t)°C for e0.42773*t seconds
So, for example, you might
maintain 71.7°C for 15 seconds maintain 64.7°C for 5 minutes maintain 63.0°C for 10 minutes
This formula is for a chicken with 12% fat. Leaner meat takes slightly less time:
maintain (78-t)°C for e0.42773*t+0.02828*(f-12) seconds, for a chicken with f% fat