Sign on

SAO/NASA ADS arXiv e-prints Abstract Service

· Find Similar Abstracts (with default settings below)
· arXiv e-print (arXiv:0905.3176)
· References in the Article
· Citations to the Article (1) (Citation History)
· Refereed Citations to the Article
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Cosmic Shear Systematics: Software-Hardware Balance
Authors:
Amara, A.; Refregier, A.; Paulin-Henriksson, S.
Publication:
eprint arXiv:0905.3176
Publication Date:
05/2009
Origin:
ARXIV
Keywords:
Astrophysics - Cosmology and Extragalactic Astrophysics
Comment:
5 pages, 3 figures. Submitted to MNRAS
Bibliographic Code:
2009arXiv0905.3176A

Abstract

Cosmic shear measurements rely on our ability to measure and correct the Point Spread Function (PSF) of the observations. This PSF is measured using stars in the field, which give a noisy measure at random points in the field. Using Wiener filtering, we show how errors in this PSF correction process propagate into shear power spectrum errors. This allows us to test future space-based missions, such as Euclid or JDEM, thereby allowing us to set clear engineering specifications on PSF variability. For ground-based surveys, where the variability of the PSF is dominated by the environment, we briefly discuss how our approach can also be used to study the potential of mitigation techniques such as correlating galaxy shapes in different exposures. To illustrate our approach we show that for a Euclid-like survey to be statistics limited, an initial pre-correction PSF ellipticity power spectrum, with a power-law slope of -3 must have an amplitude at l =1000 of less than 2 x 10^{-13}. This is 1500 times smaller than the typical lensing signal at this scale. We also find that the power spectrum of PSF size \dR^2) at this scale must be below 2 x 10^{-12}. Public code available as part of iCosmo at http://www.icosmo.org
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints