Non-linear models

class camb.nonlinear.NonLinearModel(*args, **kwargs)[source]

Abstract base class for non-linear correction models


Min_kh_nonlinear – (float64) minimum k/h at which to apply non-linear corrections

class camb.nonlinear.Halofit(*args, **kwargs)[source]

Bases: NonLinearModel

Various specific approximate non-linear correction models based on HaloFit.

  • halofit_version – (integer/string, one of: original, bird, peacock, takahashi, mead, halomodel, casarini, mead2015, mead2016, mead2020, mead2020_feedback)

  • HMCode_A_baryon – (float64) HMcode parameter A_baryon

  • HMCode_eta_baryon – (float64) HMcode parameter eta_baryon

  • HMCode_logT_AGN – (float64) HMcode parameter log10(T_AGN/K)

set_params(halofit_version='mead2020', HMCode_A_baryon=3.13, HMCode_eta_baryon=0.603, HMCode_logT_AGN=7.8)[source]

Set the halofit model for non-linear corrections.

  • halofit_version

    One of

  • HMCode_A_baryon – HMcode parameter A_baryon. Default 3.13. Used only in models mead2015 and mead2016 (and its alias mead).

  • HMCode_eta_baryon – HMcode parameter eta_baryon. Default 0.603. Used only in mead2015 and mead2016 (and its alias mead).

  • HMCode_logT_AGN – HMcode parameter logT_AGN. Default 7.8. Used only in model mead2020_feedback.

class camb.nonlinear.SecondOrderPK(*args, **kwargs)[source]

Bases: NonLinearModel

Third-order Newtonian perturbation theory results for the non-linear correction. Only intended for use at very high redshift (z>10) where corrections are perturbative, it will not give sensible results at low redshift.

See Appendix F of astro-ph/0702600 for equations and references.

Not intended for production use, it’s mainly to serve as an example alternative non-linear model implementation.