An Ideal Mass Assignment Scheme for Measuring the Power Spectrum with Fast Fourier Transforms
نویسندگان
چکیده
منابع مشابه
An Ideal Mass Assignment Scheme for Measuring the Power Spectrum with Ffts
In measuring the power spectrum of the distribution of large numbers of dark matter particles in simulations, or galaxies in observations, one has to use Fast Fourier Transforms (FFT) for calculational efficiency. However, because of the required mass assignment onto grid points in this method, the measured power spectrum 〈|δf (k)|2〉 obtained with an FFT is not the true power spectrum P (k) but...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2008
ISSN: 0004-637X,1538-4357
DOI: 10.1086/592079