Imperial College London
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ProfessorAlanHeavens

Faculty of Natural Sciences, Department of Physics

Chair in Astrostatistics
 
 
 
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Contact

 

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

 
 
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Location

 

1018EBlackett LaboratorySouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Porqueres:2021:mnras/stab3234,
author = {Porqueres, N and Heavens, A and Mortlock, D and Lavaux, G},
doi = {mnras/stab3234},
journal = {Monthly Notices of the Royal Astronomical Society},
pages = {3194--3202},
title = {Lifting weak lensing degeneracies with a field-based likelihood},
url = {http://dx.doi.org/10.1093/mnras/stab3234},
volume = {509},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We present a field-based approach to the analysis of cosmic shear data to infer jointly cosmological parameters and the dark matter distribution. This forward modelling approach samples the cosmological parameters and the initial matter fluctuations, using a physical gravity model to link the primordial fluctuations to the non-linear matter distribution. Cosmological parameters are sampled and updated consistently through the forward model, varying (1) the initial matter power spectrum, (2) the geometry through the distance-redshift relationship, and (3) the growth of structure and light-cone effects. Our approach extracts more information from the data than methods based on two-point statistics. We find that this field-based approach lifts the strong degeneracy between the cosmological matter density, Ωm, and the fluctuation amplitude, σ8, providing tight constraints on these parameters from weak lensing data alone. In the simulated four-bin tomographic experiment we consider, the field-based likelihood yields marginal uncertainties on σ8 and Ωm that are, respectively, a factor of 3 and 5 smaller than those from a two-point power spectrum analysis applied to the same underlying data.
AU  - Porqueres,N
AU  - Heavens,A
AU  - Mortlock,D
AU  - Lavaux,G
DO  - mnras/stab3234
EP  - 3202
PY  - 2021///
SN  - 0035-8711
SP  - 3194
TI  - Lifting weak lensing degeneracies with a field-based likelihood
T2  - Monthly Notices of the Royal Astronomical Society
UR  - http://dx.doi.org/10.1093/mnras/stab3234
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000756701000007&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - https://academic.oup.com/mnras/article/509/3/3194/6424956?login=true
UR  - http://hdl.handle.net/10044/1/95944
VL  - 509
ER  -
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