fastnc
fastnc is a software that compute the cosmic shear three-point correlation function (3PCF). To compute 3PCF from the underlying matter bispectrum, we need to perform a multidimensional Fourier transformation, which is difficult especially because cosmic shear 3PCF include the phase factor that makes integrand oscilates a lot. In Sugiyama+2024, we developed a novel algorithm that compute the shear 3PCF from bispectrum, using the multipole decomposition of the 3PCF and bispectrum into multipoles. The multipoles in real and Fourier space are related to each other through a 2D Hankel transform, which can be performed quite efficiently using 2D FFTLog. This software implement this idea, and enabled the cosmology inference through a joint analysis of 2+3PCF. See Sugiyama+2025 and Gomes, Sugiyama+2025 for DES and HSC application respectively.
fastlens
fastlens is an FFT based evaluation of finite source effect on microlensing. See and cite Sugiyama.
This method reduces the two-dimensional integration to one-dimensional fft on logarithmic space, which can be efficiently evaluated.
The target quantity to be evaluated is
where \(s(u;\rho)\) is the source flux profile as a function of distance from source center, \(u\).
fastlens is installable from both pip and conda:
pip install fastlens
or
conda install -c ssunao fastlens
dark_emulator_public
Dark Emulator is an emulator of cosmological dark matter halo statistics. Dark Emulator is a part of the dark quest project. This is based on Nishimichi et al. This package includes the linear power spectrum (of CAMB) emulator in itself. Dark Emulator is installable from both pip and conda:
pip install pip install dark_emulator
or
conda install -c nishimichi dark_emulator