wl_spectra_ppf module

Compute weak lensing C_ell from P(k,z) and MG D(k,z) with the Limber integral

Name: wl_spectra_ppf

File: cosmosis-standard-library/shear/spectra-ppf/interface.so

Version: 1.0

Author(s):

CosmoSIS team
Matt Becker

URL:

Cite:

Rules:

Assumptions:

The Limber integral is valid on the scales in question

Explanation

DEPRECATED: You should use the module cosmosis-standard-library/structure/projection_ppf/project_2d_ppf.py instead.

This variant of the wl_spectra module includes modified gravity
via the phenomenological D(k,z) which modifies the lensing kernel.
Compare equations 33 and 34 of http://arxiv.org/pdf/1109.4583v3.pdf

Intrinsic alignments under modified gravity are not correctly
supported; please use intrinsic_alignments=F

The Limber approximation integrates a 3D power spectrum over the radial
direction to get a 2D angular power spectrum. It is an approximation
which is only valid on smaller scales.

C_\ell = A \int_0^{\chi_1} W_1(\chi) W_2(\chi) P(k=l/\chi, z(\chi)) / chi^2 d\chi

The full integral must integrate over k(\ell) also.

For weak lensing, the power spectrum is the matter power spectrum and the two
kernel functions W depend on the redshift bins being used and the geometry.

Parts of this code and the underlying implementation of limber are based on cosmocalc:
https://bitbucket.org/beckermr/cosmocalc-public

##Parameters

These parameters can be set in the module's section in the ini parameter file.
If no default is specified then the parameter is required.

Parameter	Description
n_ell	Integer; number of log-spaced ell values to compute
ell_min	Real; minimum ell value to compute
ell_max	Real; maximum ell value to compute

##Inputs

These parameters and data are inputs to the module, either supplied as parameters by the sampler or computed by some previous module. They are loaded from the data block.

Section	Parameter	Description
modified_gravity	k_h	real vector; k/h sample points for D(k,z)
	z	real vector; z sample points for D(k,z)
	D	real 2D array; D(k,z) values at sample points
cosmological_parameters	omega_m	Real; density fraction of all matter; used in the prefactor
	h0	Real; hubble factor H0 / 100 km/s/Mpc.
distances	z	real vector; redshift values of distance samples
	d_m	real vector; comoving distnace to redshift values in units of Mpc (no factor h)
matter_power_nl	z	real vector; redshift values of P(k,z) samples
	k_h	real vector; k values of P(k,z) samples in units of Mpc/h
	P_k	real 2d array; non-linear matter power spectrum at samples in (Mpc/h)^{-3}
wl_number_density	nbin	integer; number of redshift bins
	z	real vector; redshift values of n(z) samples
	bin_	real_vector; bin n(z) values. Need not be normalized. bin_1, bin_2, bin_3, ....

##Outputs

These parameters and data are computed as outputs from the module

Section	Parameter	Description
shear_cl	ell	Sample ell values for output C_ell
	nbin	Number of redshift bins used
	bin_i_j	C_ell (no l(l+1) factor) for (auto-correlation) bin i and j. Only stores j<=i.

Wiki

cosmosis / default_modules / wl_spectra_ppf_1.0

wl_spectra_ppf module

Compute weak lensing C_ell from P(k,z) and MG D(k,z) with the Limber integral