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Searching for codes credited to 'Dolag, K.'

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[ascl:1110.011] Pacerman: Polarisation Angle CorrEcting Rotation Measure ANalysis

Pacerman, written in IDL, is a new method to calculate Faraday rotation measure maps from multi-frequency polarisation angle data. In order to solve the so called n-pi-ambiguity problem which arises from the observationally ambiguity of the polarisation angle which is only determined up to additions of n times pi, where n is an integer, we suggest using a global scheme. Instead of solving the n-pi-ambiguity for each data point independently, our algorithm, which we chose to call Pacerman solves the n-pi-ambiguity for a high signal-to-noise region "democratically" and uses this information to assist computations in adjacent low signal-to-noise areas.

[ascl:1505.032] Planck Level-S: Planck Simulation Package

The Planck simulation package takes a cosmological model specified by the user and calculates a potential CMB sky consistent with this model, including astrophysical foregrounds, and then performs a simulated observation of this sky. This Simulation embraces many instrumental effects such as beam convolution and noise. Alternatively, the package can simulate the observation of a provided sky model, generated by another program such as the Planck Sky Model software. The Planck simulation package does not only provide Planck-like data, it can also be easily adopted to mimic the properties of other existing and upcoming CMB experiments.

[submitted] vortex-p: a Helmholtz-Hodge and Reynolds decomposition algorithm for particle-based simulations

Astrophysical turbulent flows display an intrinsically multi-scale nature, making their numerical simulation and the subsequent analyses of simulated data a complex problem. In particular, two fundamental steps in the study of turbulent velocity fields are the Helmholtz-Hodge decomposition (compressive+solenoidal; HHD) and the Reynolds decomposition (bulk+turbulent; RD). These problems are relatively simple to perform numerically for uniformly-sampled data, such as the one emerging from Eulerian, fix-grid simulations; but their computation is remarkably more complex in the case of non-uniformly sampled data, such as the one stemming from particle-based or meshless simulations. In this paper, we describe, implement and test vortex-p, a publicly available tool evolved from the vortex code, to perform both these decompositions upon the velocity fields of particle-based simulations, either from smoothed particle hydrodynamics (SPH), moving-mesh or meshless codes. The algorithm relies on the creation of an ad-hoc adaptive mesh refinement (AMR) set of grids, on which the input velocity field is represented. HHD is then addressed by means of elliptic solvers, while for the RD we adapt an iterative, multi-scale filter. We perform a series of idealised tests to assess the accuracy, convergence and scaling of the code. Finally, we present some applications of the code to various SPH and meshless finite-mass (MFM) simulations of galaxy clusters performed with OpenGadget3, with different resolutions and physics, to showcase the capabilities of the code.