RESEARCH WORK

NOCTUA Suite of Simulations

Under construction...

Colliding Galaxies in a (Nut)Shell

MSc Thesis Project (2022); Petersson et al. (2023)

I run numerical simulations of two merging disc galaxies and their formation into a shell galaxy, using the RAMSES code (Teyssier, 2002). By conducting a parameter survey, I explore different sets of parameters to find an orbtial configuration favourable for shell formation. Based on that, I perform an idealised high-resolution merger simulation, and follow its formation into a shell galaxy. I then analyse how the merger-driven star formation activity evolves throughout time, within the system, what the physical conditions are for it, and how it relates to the formation of shells.

Simulation of two colliding disc galaxies (1:2 mass ratio), merging into a shell galaxy. The gas of the two systems is shown in blue, while old and newly formed stellar populations are shown in grey and white, respectively.

Supervisor: Florent Renaud
Thesis: LUP Student Papers
Publication: ArXiv, MNRAS

The Disturbed Outer Milky Way Disc

Summer Research Project (2021); McMillan & Petersson et al. (2022)

In Gaia Early Data Release 3, a break in the vertical angular momentum-velocity plane can be disguished (Gaia Collaboration et al., 2021), a break that is suspected to have a dynamical origin. As part of my summer project, I explore the possibility for a dynamical origin by conducting a series of N-body simulations of a Milky Way-like galaxy being perturb by a Sagittarius-like dwarf galaxy impact using the RAMSES code (Teyssier, 2002).

Simulation of a Milky Way-like galaxy being perturb by a Sagittarius-like dwarf galaxy impact (represented by a point particle).

Supervisor: Paul McMillan
Publication: ArXiv, MNRAS

Capture of Interstellar Objects in the Solar System

BSc Thesis Project (2020)

I estimate the capture rate of interstellar objects (ISOs) in the Solar system, using the N-body code MERCURY (Chambers, 1999). From this, I analyse the orbital properties of captured ISOs and how they get captured and/or ejected.

Supervisor: Daohai Li
Thesis: LUP Student Papers

TECHNICAL WORK

The VATPY Code

Vatpy (Visualisation of Arepo in the Terminal using PYthon) is a light-weight, highly customisable, visualisation tool-kit for astrophysical simulations performed using the Arepo code (Springel 2010).

Many of its functionalities can be generally applied to simulations made by Arepo (as long as the output is in HDF5-format), however, more specific capabilities, such as creating visual maps of the gas chemistry, is at the moment only adapted to simulations run using the ArepoNoctua numerical framework (Petersson et al. 2025).

At the moment, Vatpy is only accesible via the NOCTUA project page, and is therefore only available to invited members. If you wish to use Vatpy in your own work and be a part of the development of the code, or would just like some more information, please reach out via e-mail.