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Cosmic Shear with the CFHT

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 نشر من قبل Yannick Mellier
 تاريخ النشر 2000
  مجال البحث فيزياء
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We present results of our cosmic shear survey in progress at the Canada- France-Hawaii Telescope (CFHT). We analysed 1.7 sq. degrees of data, out of which we measured a significant correlation of galaxy shape-orientation over several arcmin scale. We present measurements of the variance of the shear $<gamma^2>$ and of the correlation functions $<e_r(theta)e_r(0)>$, $<e_t(theta)e_t(0)>$. The signal is consistent with gravitational lensing by large scale structures predictions. The level of residual systematics after PSF correction is small compared to our measured signal. We outline several evolutions of our work by using additional data covering 9 sq. degrees.



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