Left panel: the fit to σ of the PS with the best parameters derived from the sigmoid function. The best-fit parameters to this function are noted in the first row of Table 1. Right panel: the fit to σ of the CS with the best parameters derived from a piecewise function. The data points below z_cut = 3.01 are best fit with a fourth-order polynomial, while the data points above z_cut are best fit with a sigmoid. The best-fit parameters to these functions are noted in the second and third rows of Table 1.