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arXiv · 2107.06147

QTRAJ 1.0: A Lindblad equation solver for heavy-quarkonium dynamics

Hisham Ba Omar·Miguel Ángel Escobedo·Ajaharul Islam·Michael Strickland·Sabin Thapa·Peter Vander Griend·Johannes Heinrich Weber
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Abstract

We introduce an open-source package called QTraj that solves the Lindblad equation for heavy-quarkonium dynamics using the quantum trajectories algorithm. The package allows users to simulate the suppression of heavy-quarkonium states using externally-supplied input from 3+1D hydrodynamics simulations. The code uses a split-step pseudo-spectral method for updating the wave-function between jumps, which is implemented using the open-source multi-threaded FFTW3 package. This allows one to have manifestly unitary evolution when using real-valued potentials. In this paper, we provide detailed documentation of QTraj 1.0, installation instructions, and present various tests and benchmarks of the code.

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Hisham Ba Omar, Miguel Ángel Escobedo, Ajaharul Islam, Michael Strickland, Sabin Thapa, Peter Vander Griend, Johannes Heinrich Weber. 2021-07-13. QTRAJ 1.0: A Lindblad equation solver for heavy-quarkonium dynamics. https://doi.org/10.1016/j.cpc.2021.108266

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