The class is libLSS/physics/bias/double_power_law.hpp, class is LibLSS::bias::DoubleBrokenPowerLaw.

This class implements the double power law bias model. Its corresponding mathematical model is {$$N_g = \bar{n} \frac{\rho_m^\alpha}{1 + (\rho_m/\rho_0)^{\alpha-\beta}},$$} with {$\rho_m = 1+\delta_m$}, {$\bar{n}$} a normalization constant, {$\alpha$} the power law scaling, {$\beta$} the second power law scaling, {$\rho_0$} the threshold between the two power law.