Source code for lenstronomy.LensModel.Profiles.nfw_mass_concentration

__author__ = 'sibirrer'

# this file contains a class to compute the Navaro-Frank-White function in mass/kappa space
from lenstronomy.LensModel.Profiles.nfw import NFW
from lenstronomy.Cosmo.lens_cosmo import LensCosmo
from lenstronomy.LensModel.Profiles.base_profile import LensProfileBase

__all__ = ['NFWMC']


[docs]class NFWMC(LensProfileBase): """ this class contains functions parameterises the NFW profile with log10 M200 and the concentration rs/r200 relation are: R_200 = c * Rs ATTENTION: the parameterization is cosmology and redshift dependent! The cosmology to connect mass and deflection relations is fixed to default H0=70km/s Omega_m=0.3 flat LCDM. It is recommended to keep a given cosmology definition in the lens modeling as the observable reduced deflection angles are sensitive in this parameterization. If you do not want to impose a mass-concentration relation, it is recommended to use the default NFW lensing profile parameterized in reduced deflection angles. """ param_names = ['logM', 'concentration', 'center_x', 'center_y'] lower_limit_default = {'logM': 0, 'concentration': 0.01, 'center_x': -100, 'center_y': -100} upper_limit_default = {'logM': 16, 'concentration': 1000, 'center_x': 100, 'center_y': 100} def __init__(self, z_lens, z_source, cosmo=None, static=False): """ :param z_lens: redshift of lens :param z_source: redshift of source :param cosmo: astropy cosmology instance :param static: boolean, if True, only operates with fixed parameter values """ self._nfw = NFW() if cosmo is None: from astropy.cosmology import FlatLambdaCDM cosmo = FlatLambdaCDM(H0=70, Om0=0.3, Ob0=0.05) self._lens_cosmo = LensCosmo(z_lens=z_lens, z_source=z_source, cosmo=cosmo) self._static = static super(NFWMC, self).__init__() def _m_c2deflections(self, logM, concentration): """ :param logM: log10 mass in M200 stellar masses :param concentration: halo concentration c = r_200 / r_s :return: Rs (in arc seconds), alpha_Rs (in arc seconds) """ if self._static is True: return self._Rs_static, self._alpha_Rs_static M = 10 ** logM Rs, alpha_Rs = self._lens_cosmo.nfw_physical2angle(M, concentration) return Rs, alpha_Rs
[docs] def set_static(self, logM, concentration, center_x=0, center_y=0): """ :param logM: :param concentration: :param center_x: :param center_y: :return: """ self._static = True M = 10 ** logM self._Rs_static, self._alpha_Rs_static = self._lens_cosmo.nfw_physical2angle(M, concentration)
[docs] def set_dynamic(self): """ :return: """ self._static = False if hasattr(self, '_Rs_static'): del self._Rs_static if hasattr(self, '_alpha_Rs_static'): del self._alpha_Rs_static
[docs] def function(self, x, y, logM, concentration, center_x=0, center_y=0): """ :param x: angular position :param y: angular position :param Rs: angular turn over point :param alpha_Rs: deflection at Rs :param center_x: center of halo :param center_y: center of halo :return: """ Rs, alpha_Rs = self._m_c2deflections(logM, concentration) return self._nfw.function(x, y, alpha_Rs=alpha_Rs, Rs=Rs, center_x=center_x, center_y=center_y)
[docs] def derivatives(self, x, y, logM, concentration, center_x=0, center_y=0): """ returns df/dx and df/dy of the function (integral of NFW) """ Rs, alpha_Rs = self._m_c2deflections(logM, concentration) return self._nfw.derivatives(x, y, Rs, alpha_Rs, center_x, center_y)
[docs] def hessian(self, x, y, logM, concentration, center_x=0, center_y=0): """ returns Hessian matrix of function d^2f/dx^2, d^2/dxdy, d^2/dydx, d^f/dy^2 """ Rs, alpha_Rs = self._m_c2deflections(logM, concentration) return self._nfw.hessian(x, y, Rs, alpha_Rs, center_x, center_y)