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arXiv · 2507.21239

mcdust: A 2D Monte Carlo code for dust coagulation in protoplanetary disks

Abstract

mcdust is a parallel simulation code for dust evolution in protoplanetary disks. The code is written in FORTRAN90 and parallelised with OpenMP. The code models dust collisional evolution and transport in the vertical and radial directions. The currently included collisional outcomes are dust growth by sticking, fragmentation of dust particles and erosion, where a small particle chips a portion of the large particle. We employ a representative particle approach to track a limited number of particles instead of tracking every particle, saving computational time. We have a static power-law gas disk with temperature assumed to be vertically isothermal. Dust coagulation depends on the local gas properties, and therefore, we bin particles into grids and perform collisions. We make use of an adaptive grid approach where we make sure that each cell has an equal number of representative particles. This guarantees that there are always sufficient particles to resolve the physics of collisions. The code resolves dust coagulation in 2D(r-z). To access the documentation of the code, see https://mcdust.readthedocs.io/ .

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Vignesh Vaikundaraman, Nerea Gurrutxaga, Joanna Drążkowska. 2025-07-28. mcdust: A 2D Monte Carlo code for dust coagulation in protoplanetary disks. https://arxiv.org/abs/2507.21239

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