Imperial College London
Portrait Picture

ProfessorAlanHeavens

Faculty of Natural Sciences, Department of Physics

Chair in Astrostatistics
 
 
 
//

Contact

 

+44 (0)20 7594 2930a.heavens Website

 
 
//

Location

 

1018EBlackett LaboratorySouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Alsing:2015:mnras/stv2501,
author = {Alsing, J and Heavens, A and Jaffe, AH and Kiessling, A and Wandelt, B and Hoffmann, T},
doi = {mnras/stv2501},
journal = {Monthly Notices of the Royal Astronomical Society},
pages = {4452--4466},
title = {Hierarchical cosmic shear power spectrum inference},
url = {http://dx.doi.org/10.1093/mnras/stv2501},
volume = {455},
year = {2015}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We develop a Bayesian hierarchical modelling approach for cosmic shear power spectrum inference, jointly sampling from the posterior distribution of the cosmic shear field and its (tomographic) power spectra. Inference of the shear power spectrum is a powerful intermediate product for a cosmic shear analysis, since it requires very few model assumptions and can be used to perform inference on a wide range of cosmological models a posteriori without loss of information. We show that joint posterior for the shear map and power spectrum can be sampled effectively by Gibbs sampling, iteratively drawing samples from the map and power spectrum, each conditional on the other. This approach neatly circumvents difficulties associated with complicated survey geometry and masks that plague frequentist power spectrum estimators, since the power spectrum inference provides prior information about the field in masked regions at every sampling step. We demonstrate this approach for inference of tomographic shear E-mode, B-mode and EB-cross power spectra from a simulated galaxy shear catalogue with a number of important features; galaxies distributed on the sky and in redshift with photometric redshift uncertainties, realistic random ellipticity noise for every galaxy and a complicated survey mask. The obtained posterior distributions for the tomographic power spectrum coefficients recover the underlying simulated power spectra for both E- and B-modes.
AU  - Alsing,J
AU  - Heavens,A
AU  - Jaffe,AH
AU  - Kiessling,A
AU  - Wandelt,B
AU  - Hoffmann,T
DO  - mnras/stv2501
EP  - 4466
PY  - 2015///
SN  - 1365-2966
SP  - 4452
TI  - Hierarchical cosmic shear power spectrum inference
T2  - Monthly Notices of the Royal Astronomical Society
UR  - http://dx.doi.org/10.1093/mnras/stv2501
UR  - http://hdl.handle.net/10044/1/33001
VL  - 455
ER  -
Download