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arXiv · 1703.03284

Model-independent partial wave analysis using a massively-parallel fitting framework

Liang Sun·Rafael Aoude·Alberto Correa Dos Reis·Michael David Sokoloff
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Abstract

The functionality of GooFit, a GPU-friendly framework for doing maximum-likelihood fits, has been extended to extract model-independent S-wave amplitudes in three-body decays such as $D^+ \to h^+h^+h^-$. A full amplitude analysis is done where the magnitudes and phases of the S-wave amplitudes are anchored at a finite number of $m^2(h^+h^-)$ control points, and a cubic spline is used to interpolate between these points. The amplitudes for P-wave and D-wave intermediate states are modeled as spin-dependent Breit-Wigner resonances. GooFit uses the Thrust library, with a CUDA backend for NVIDIA GPUs and an OpenMP backend for threads with conventional CPUs. Performance on a variety of platforms is compared. Executing on systems with GPUs is typically a few hundred times faster than executing the same algorithm on a single CPU.

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Liang Sun, Rafael Aoude, Alberto Correa Dos Reis, Michael David Sokoloff. 2017-02-19. Model-independent partial wave analysis using a massively-parallel fitting framework. https://doi.org/10.1088/1742-6596/898/7/072025

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