x-cut Cosmic Shear: Optimally Removing Sensitivity to Baryonic and Nonlinear Physics with an Application to the Dark Energy Survey Year 1 Shear Data. (arXiv:2007.00675v1 [astro-ph.CO])
<a href="http://arxiv.org/find/astro-ph/1/au:+Taylor_P/0/1/0/all/0/1">Peter L. Taylor</a> (JPL), <a href="http://arxiv.org/find/astro-ph/1/au:+Bernardeau_F/0/1/0/all/0/1">Francis Bernardeau</a> (IAP, IPT), <a href="http://arxiv.org/find/astro-ph/1/au:+Huff_E/0/1/0/all/0/1">Eric Huff</a> (JPL)
We present a new method, called x-cut cosmic shear, which optimally removes
sensitivity to poorly modeled scales from the two-point cosmic shear signal. We
show that the x-cut cosmic shear covariance matrix can be computed from the
correlation function covariance matrix in a few minutes, enabling a likelihood
analysis at virtually no additional computational cost. Further we show how to
generalize x-cut cosmic shear to galaxy-galaxy lensing. Performing an x-cut
cosmic shear analysis of the Dark Energy Survey Year 1 (DESY1) shear data, we
reduce the error on S8 by 20% relative to a correlation function analysis,
while showing our constraints are robust to different baryonic feedback models.
Largely driven by information at small angular scales, our result, S8 = 0.734
plus/minus 0.038, yields a 2.6 sigma tension with the Planck Legacy analysis of
the cosmic microwave background. As well as alleviating baryonic modelling
uncertainties, our method can be used to optimally constrain a large number of
theories of modified gravity where computational limitations make it infeasible
to model the power spectrum down to extremely small scales. The key parts of
our code are made publicly available.
We present a new method, called x-cut cosmic shear, which optimally removes
sensitivity to poorly modeled scales from the two-point cosmic shear signal. We
show that the x-cut cosmic shear covariance matrix can be computed from the
correlation function covariance matrix in a few minutes, enabling a likelihood
analysis at virtually no additional computational cost. Further we show how to
generalize x-cut cosmic shear to galaxy-galaxy lensing. Performing an x-cut
cosmic shear analysis of the Dark Energy Survey Year 1 (DESY1) shear data, we
reduce the error on S8 by 20% relative to a correlation function analysis,
while showing our constraints are robust to different baryonic feedback models.
Largely driven by information at small angular scales, our result, S8 = 0.734
plus/minus 0.038, yields a 2.6 sigma tension with the Planck Legacy analysis of
the cosmic microwave background. As well as alleviating baryonic modelling
uncertainties, our method can be used to optimally constrain a large number of
theories of modified gravity where computational limitations make it infeasible
to model the power spectrum down to extremely small scales. The key parts of
our code are made publicly available.
http://arxiv.org/icons/sfx.gif
