English

Detection of Cosmic Shear with the William Herschel Telescope

Astrophysics 2007-05-23 v1

Abstract

Gravitational lensing by large-scale structure induces weak coherent alignments in the shapes of background galaxies. Here we present evidence for the detection of this `cosmic shear' at the 3.4 sigma significance level with the William Herschel Telescope. Analysis and removal of notable systematic effects, such as shear induced by telescope optics and smearing by tracking and seeing, are conducted in order to recover the physical weak shear signal. Positive results for shear recovery on realistic simulated data are presented, enhancing confidence in the measurement method. The detection of cosmic shear is statistically characterised, and its cosmological significance is discussed.

Keywords

Cite

@article{arxiv.astro-ph/0008248,
  title  = {Detection of Cosmic Shear with the William Herschel Telescope},
  author = {David Bacon and Alexandre Refregier and Richard Ellis},
  journal= {arXiv preprint arXiv:astro-ph/0008248},
  year   = {2007}
}

Comments

4 pages, including 3 figures. To appear in Proceedings of XXth Moriond Astrophysics Meeting, "Cosmological Physics with Gravitational Lensing", eds. J.-P. Kneib, Y. Mellier, M. Moniez and J. Tran Thanh Van