Reionization models

class camb.reionization.ReionizationModel(*args, **kwargs)[source]

Abstract base class for reionization models.


Reionization – (boolean) Is there reionization? (can be off for matter power which is independent of it)

class camb.reionization.TanhReionization(*args, **kwargs)[source]

Bases: ReionizationModel

This default (unphysical) tanh x_e parameterization is described in Appendix B of arXiv:0804.3865

  • use_optical_depth – (boolean) Whether to use the optical depth or redshift paramters

  • redshift – (float64) Reionization redshift if use_optical_depth-False

  • optical_depth – (float64) Optical depth if use_optical_depth=True

  • delta_redshift – (float64) Duration of reionization

  • fraction – (float64) Reionization fraction when complete, or -1 for full ionization of hydrogen and first ionization of helium.

  • include_helium_fullreion – (boolean) Whether to include second reionization of helium

  • helium_redshift – (float64) Redshift for second reionization of helium

  • helium_delta_redshift – (float64) Width in redshift for second reionization of helium

  • helium_redshiftstart – (float64) Include second helium reionizatio below this redshift

  • tau_solve_accuracy_boost – (float64) Accuracy boosting parameter for solving for z_re from tau

  • timestep_boost – (float64) Accuracy boosting parameter for the minimum number of time sampling steps through reionization

  • max_redshift – (float64) Maxmimum redshift allowed when mapping tau into reionization redshift

get_zre(params, tau=None)[source]

Get the midpoint redshift of reionization.

  • paramsmodel.CAMBparams instance with cosmological parameters

  • tau – if set, calculate the redshift for optical depth tau, otherwise uses curently set parameters


reionization mid-point redshift

set_tau(tau, delta_redshift=None)[source]

Set the optical depth

  • tau – optical depth

  • delta_redshift – delta z for reionization



set_zrei(zrei, delta_redshift=None)[source]

Set the mid-point reionization redshift

  • zrei – mid-point redshift

  • delta_redshift – delta z for reionization