SZpack is a numerical library which allows fast and precise computation of the Sunyaev-Zeldovich (SZ) signal for hot, moving clusters of galaxies. Both explicit numerical integration as well as approximate representation of the SZ signals can be obtained. Variations of the electron temperature and bulk velocity along the line-of-sight can be included. SZpack allows very fast and precise (<~0.001% at frequencies h nu <~ 30kT_g and electron temperature kTe ~ 75 keV) computation and its accuracy practically eliminates uncertainties related to more expensive numerical evaluation of the Boltzmann collision term. It furthermore cleanly separates kinematic corrections from scattering physics, effects that previously have not been clarified.

PoPE (Population Profile Estimator) analyzes spatial distribution or internal spatial structure problems of samples of astronomical systems. This population-based Bayesian inference model uses the conditional statistics of spatial profile of multiple observables assuming the individual observations are measured with errors of varying magnitude. Assuming the conditional statistics of the observables can be described with a multivariate normal distribution, the model reduces to the conditional average profile and conditional covariance between all observables. The method consists of two steps: (1) reconstructing the average profile using non-parametric regression with Gaussian Processes and (2) estimating the property profiles covariance given a set of independent variable. PoPE is computationally efficient and capable of inferring average profiles of a population from noisy measurements without stacking and binning nor parameterizing the shape of the average profile.