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

TL;DR

QTraj 1.0 is an open-source solver for heavy-quarkonium dynamics based on the Lindblad equation, enabling realistic simulations of quarkonium suppression in quark-gluon plasma using quantum trajectories and hydrodynamic inputs.

Contribution

This paper introduces QTraj 1.0, a novel open-source package that implements a Lindblad equation solver with a split-step pseudo-spectral method for heavy-quarkonium simulations.

Findings

Provides detailed documentation and benchmarks.

Enables simulation of quarkonium suppression with hydrodynamic data.

Uses a split-step pseudo-spectral method for unitary evolution.

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.