The equation for the compensated response of ramp reactivity is
$$\rho(t)=\alpha(t-t_0)-b\int^t_{t_0}n(t’)dt’$$
Which reduces to
$$\frac{d\rho}{dt}=a-bn(t)$$
The reactivity feedback is represented by $bn(t)$ and the $a$ term is the impressed reactivity.
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