Detection of Cosmic Shear with the William Herschel Telescope
نویسندگان
چکیده
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 3.4σ 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.
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