Hierarchical cosmic shear power spectrum inference
نویسندگان
چکیده
منابع مشابه
Cosmic Shear and Power Spectrum Normalization with the Hubble Space Telescope
Weak lensing by large-scale structure provides a direct measurement of matter fluctuations in the universe. We report a measurement of this ‘cosmic shear’ based on 271 WFPC2 archival images from the Hubble Space Telescope Medium Deep Survey (MDS). Our measurement method and treatment of systematic effects were discussed in an earlier paper. We measure the shear variance on scales ranging from 0...
متن کاملPower spectrum from weak-shear data
We demonstrate that the aperture mass as a measure for cosmic shear closely approximates (to better than ≈ 5%) the scaled and shifted power spectrum of the projected mass density. This cosmological weak-lensing information can thus be used to directly infer the projected matter power spectrum with high accuracy. As an application, we show that aperturemass observations can be used to constrain ...
متن کاملPower Laws and the Cosmic Ray Energy Spectrum
Two separate statistical tests are applied to the AGASA and preliminary Auger Cosmic Ray Energy spectra in an attempt to find deviation from a pure power-law. The first test is constructed from the probability distribution for the maximum event of a sample drawn from a power-law. The second employs the TP-statistic, a function defined to deviate from zero when the sample deviates from the power...
متن کاملCosmic string formation and the power spectrum of field configurations.
We examine the statistical properties of defects formed by the breaking of a U(1) symmetry when the Higgs field has a power spectrum P (k) ∝ kn. We find a marked dependence of the amount of infinite string on the spectral index n and empirically identify an analytic form for this quantity. We also confirm that this result is robust to changes in the definition of infinite string. It is possible...
متن کاملCosmic shear and biasing
The correlation between cosmic shear as measured by the image distortion of high-redshift galaxies and the number counts of foreground galaxies is calculated. For a given power spectrum of the cosmic density fluctuations, this correlation is proportional to the bias factor, which can thus directly be measured. In addition, this correlation provides a firstorder measure of cosmic shear and is th...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2015
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/stv2501