NCTS-TCA Summer Student Program 2025
理論計算天文暑期學校

Europa, one of Jupiter’s icy moons, is a prime candidate for harboring extraterrestrial life due to its subsurface ocean. Plumes of water vapor erupting from its surface offer a unique opportunity to study its composition without the need to drill through the thick ice shell. However, these plumes consist of more than just water; they contain a complex mixture of chemical species that provide valuable insights into Europa’s internal processes.
This project focuses on investigating the chemical diversity in Europa’s plumes by modeling the photodissociation products of water (OH, O, H) and minor species as they interact with the predominant water vapor. We will explore how molecular collisions affect the morphology of the plumes, including the width and angular distribution of various species. These factors are influenced by molecular weights, collisional cross-sections, and the kinetic energy derived from photodissociation, providing insights into how different gas species expand and evolve in space. By enhancing our understanding of Europa's plume dynamics, this research contributes to ongoing and future missions, such as Europa Clipper and JUICE, aiding in the analysis of the chemical signatures of an extraterrestrial ocean world.

Pre-requisites: Major in the STEM fields; Basic Programming
Keywords: Simulation, Icy moon, Plume, Ion Chemistry
Location: NTNU

Europa's plumes present a unique opportunity to study the interactions with Jupiter's intense magnetosphere. While much research has focused on the neutral gas components of these plumes, their ionospheres remain largely unexplored. Understanding the ionized species within these plumes is crucial for interpreting upcoming observations from space missions, such as Europa Clipper.
This project aims to examine various ionization processes, including electron-impact ionization, photoionization, and charge-exchange reactions, in order to assess their contributions to the plume's ionized environment. A key focus of the study will be on ion-molecular chemistry, particularly the formation of water-group ion clusters such as H₃O⁺. Additionally, by incorporating diffusion processes, we will investigate how ionized species evolve and interact with Jupiter's magnetospheric plasma. By enhancing our understanding of plume ionospheres on both local and global scales, this research will provide valuable insights for future spacecraft missions and contribute to broader studies of planetary ionospheres and space plasma interactions.

Pre-requisites: Major in the STEM fields; basic programming
Keywords: Icy Moon, Plume, Ion-Chemistry, Diffusion, Magnetosphere
Location: NTNU

Relativistic jets and outflows are commonly observed in black holes. Understanding their mechanisms requires a detailed exploration of the accretion process and models surrounding BHs. This project introduces students to the fundamentals of magnetized accretion and jet-launching processes. Instead of running full-fledged GRMHD simulations, students will focus on analyzing pre-generated simulation data and working with simplified models to study:
1)The basic relationship between magnetization (σ), beta plasma, and jet formation.
2)The impact of initial magnetic field configurations on disk structure and dynamics.
3)Trends in jet collimation and power using visualization tools like ParaView or Python-based analysis scripts.
The goal is to provide students with hands-on experience in understanding the interplay between accretion flow properties and magnetic fields while developing essential data analysis and visualization skills.

Pre-requisites: Basic understanding of black hole astrophysics; Basic programming (e.g., basic knowledge of C/C++ or Python is preferred but not required)
Keywords: GRMHD, Black hole jets, accretion disks.
Location: NTHU or remote

Magnetic fields play a critical role in galaxies, but their origin remains an open question. While the dynamo theory offers a theoretical framework for amplifying magnetic fields from initial seeds, the details are still an active area of research. In this project, the student will analyze a suite of high-resolution magnetohydrodynamical simulations of isolated galaxies to investigate how magnetic fields can be generated by the interplay between stellar feedback, turbulence, and galactic rotation. The student will gain basic knowledge of the dynamo theory, learn how to make physical interpretations from simulation data, and understand the numerics and limitations of simulations.

Pre-requisites: General astronomy, basic knowledge of Python, C, and Linux
Keywords: Galaxies, Interstellar medium, Magnetohydrodynamical simulations
Location: NTU or remote

We develop hydrodynamic and magnetohydrodynamic codes and solvers for astrophysical problems in the ASIAA CompAS project. We invite students to explore and validate state-of-the-art numerical codes and solvers made with fundamental numerical methods and physics under active development. These codes and solvers range from the Newtonian to General Relativistic regimes occurring from young stars to black holes. The students will obtain hands-on experience testing the accuracy and performance of numerical methods for HD, MHD, and particle problems for their validation and benchmarks. We look for highly motivated students interested in numerical methods, code development techniques, their science verifications, potential applications, and explorations and utilization of machine learning/AI approaches. Actual projects will be assigned commensurate with students' levels of academic background, preparation and readiness. The experiences obtained will prove very helpful in future career development in science, engineering, or computing, in addition to astronomy and astrophysics.

Pre-requisites: Good knowledge of Mathematics, and Physics, with any of these programming languages: Python, C/C++ or Fortran College-level physics curricula, applied mathematics, or mathematical methods Ability to read, write, and communicate orally in English Knowledge of Python, Matlab, or interactive plotting tools.
Keywords: Black Holes, CompAS, Computational Astrophysics, Computational Fluid Mechanics, Hydrodynamics, Machine Learning, Magnetohydrodynamics, Numerical Astrophysics, Numerical methods, Particle-In-Cell, Plasma Physics, Young Stars, AI
Location: ASIAA/NTU

Galaxy cluster mergers drive shocks and turbulence in the intracluster medium (ICM), shaping the thermodynamic structure of the cluster. The Sausage cluster (CIZA J2242.8+5301) has been extensively studied, with X-ray and radio observations revealing complex structures. To better understand the role of temperature variations in shaping the observed X-ray morphology, we will refine the temperature structure in simulations while keeping the large-scale merger parameters fixed. This project will build upon the best merger scenario from van Weeren et al. (2011, MNRAS, 418, 230) by exploring different initial temperature profiles and distributions for the merging subclusters. Project Aim:
1. Modify and implement different initial temperature combinations and profiles for subclusters in hydrodynamical simulations.
2. Analyze the resulting simulated X-ray maps and compare them with observational data.
3. Quantify morphological differences using asymmetry and substructure measures.
4. Investigate how refined temperature structures influence the observed X-ray brightness and temperature distributions.

Pre-requisites: Basic knowledge of galaxy clusters and intracluster medium physics. Basic coding skills in Python (for data analysis and visualisation). Familiarity with numerical simulations (e.g., hydrodynamical codes) is beneficial but not mandatory.
Keywords: Galaxy clusters, intracluster medium, hydrodynamical simulations, X-ray astronomy, merger dynamics, shock heating
Location: NTHU

Neutrinos play a decisive role in understanding how the collapse of massive stars turns from an implosion to an explosion. Correctly accounting for their propagation, interaction with ordinary matter, and flavor evolution is crucial. The selected student will learn about the neutrino driven mechanism, which is the current paradigm to explain supernova explosions. The focus is on the effect of neutrino flavor conversions. The student will work with data from numerical simulations of core-collapse supernovae and explore what we can learn from the future detection of neutrinos originating in a galactic supernova.

Pre-requisites: Quantum Mechanics, Basic programming (Python, C/C++, Fortran)
Keywords: Core-Collapse Supernovae, Neutrinos, neutron star, neutrino flavor conversions
Location: ASIoP

Molecular clouds are the birthplaces of stars and play a fundamental role in the evolution of galaxies. Understanding their physical properties —such as density, temperature, and velocity — is crucial for interpreting observational data and improving theoretical models of star formation. In this project, the student will analyze numerical simulations of molecular clouds to extract gas properties, identify substructures, and compare the results with observational data. This will involve: Learning fundamental concepts about the ISM, molecular clouds, and the processes involved in star formation. Gaining experience in working with astrophysical simulations. Applying analysis techniques to characterize gas properties and substructures within molecular clouds. Comparing the extracted properties with real astronomical data.

Pre-requisites: Undergraduate students in physics (preferably in their final years), Python programming skills.
Keywords: Molecular clouds, numerical simulations
Location: NTNU or remote

The N-body problem is one of the oldest problems in physics, first described mathematically by Isaac Newton. This problem consists of solving for the motion of N particles interacting gravitationally. Nowadays, we must solve this problem to understand the evolution of planetary systems or galaxies. In this project, we will develop a new public N-body code which will potentially be used widely by the community of astronomers. We will optimize the growth of error in the code and utilize special numerical methods like symplectic methods.

Pre-requisites: This project requires strong programming skills in any language of the student's choice, but with preference for C and MATLAB. Some basic knowledge of classical mechanics is desirable.
Keywords: N-body problem, classical mechanics, codes
Location: At least half of the time, this project will be supervised remotely. The other half will be at NTNU.

Diffuse cocoons are found in many astrophysical systems, typically surrounding stars and galaxies that emit both radiation and energetic particles. These cocoons are not only illuminated by radiation, but are also continuously bombarded by highly energetic particles, making them environments to exhibit the Neupert effect. The Neupert effect is an empirical temporal correlation between the UV/soft X-ray emission and non-thermal hard X-ray emission. It is frequently seen in solar and stellar flares, indicating that accelerated particles deposit energy into the plasma, causing it to heat up and radiate at lower energies. In a similar manner, some processes in starburst galaxies and AGN may also show Neupert effects. The correlations between the flares provide valuable insights into the system’s underlying physics, including its geometry, energy release mechanisms, and particle acceleration processes.
In this project, the student will build simple cases of flares and derive the corresponding light curves analytically. Next they will model various types of flares using a Monte Carlo approach to generate synthetic light curves. These simulated light curves will serve as theoretical templates for comparison with observational data, helping in improving our understanding of the Neupert effect in astrophysical systems.

Pre-requisites: Basic knowledge in calculus (e.g. to solve ODEs). Familiar with Python.
Keywords: Flares, high-energy particles, thermal emission, non-thermal emission
Location: NTHU or NTNU or remote

Recent JWST observations have revealed many gas lines and dust features in the near-IR. Students will analyze the new JWST data by modeling the atomic and molecular lines. They will learn atomic and molecular spectroscopy along with their excitation conditions. Students will work with the new JWST observations and state-of-the-art models.

Pre-requisites: Calculus, Python
Keywords: Star formation, planet formation, radiative transfer, JWST
Location: NTHU or remote

JWST has delivered high-quality observations of dust and gas toward planet-forming disks. The current models have difficulties reproducing these observations. Students will analyze new JWST data toward protoplanetary disks with state-of-the-art radiative transfer models.

Pre-requisites: Calculus, Python
Keywords: Planet formation, radiative transfer, JWST
Location: NTHU or remote

Fuzzy dark matter (FDM) has emerged as a promising alternative to cold dark matter (CDM), offering potential solutions to small-scale challenges while preserving large-scale consistency. The FDM model, characterized by ultralight bosons with masses around 1e-22 eV, exhibits distinctive wave-like structures, including a central solitonic core and an extended granular halo. In this project, we will use high-resolution numerical simulations with the state-of-the-art FDM code GAMER-2 to investigate how stochastic density fluctuations in the granular halo perturb and dynamically heat cold, thin stellar streams in the Milky Way. The results will provide insights into the impact of FDM on galactic substructures and offer constraints on the boson mass.

Pre-requisites: Calculus; Basic knowledge of C and Python
Keywords: Dark Matter, Galaxies, Numerical Simulations
Location: NTU or remote

Protoplanetary disks—the birth sites of planets—are likely prone to several hydrodynamical instabilities that drive turbulence and structure formation, directly affecting planet formation. One candidate, the "convective overstability" (COS), may develop in the planet-forming regions of protoplanetary disks. However, the COS has mainly been studied under idealized settings, so its efficiency in realistic disks is still unclear. In this project, the student will test the robustness of the COS against different numerical models, focusing on the treatment of vertical boundaries. To this end, the student will carry out simulations using the Python-based Dedalus code, the GPU-enabled Idefix code, or both, to study the non-linear evolution of the COS in 2D and 3D. The student will run simulations, analyze and interpret the data, and write results.
The student will have access to the Kawas cluster at ASIAA, the ASGC clusters at Academia Sinica, and CPU and GPU clusters at the National Center for High-performance Computing. Successful completion of the project is expected to lead to publication.

Pre-requisites: Mandatory: Mathematical or physical sciences, basic calculus and partial differential equations, Python or other programming languages, English communication skills. Useful: Fluid dynamics, high-performance computing
Keywords: Astrophysical Fluid Dynamics, Computational Astrophysics, Numerical Simulations, Planet Formation, Protoplanetary Disks, Theoretical Astrophysics
Location: ASIAA/NTU

The student will perform hydrodynamical simulations with the GAMER code to study the collapse of a prestellar core. The purpose of this project is to follow the dust particles that have been very close to the protostar (therefore severely heated) and see how they are ejected in the outflow, and how fast they cool down. This can help us understand the origin of refractive minerals found in meteorites and cometary materials, and tell us crucial information of matter transport in the Solar System during its formation phase. The student will simulate the collapsing prestellar core with seeded tracer particles. By varying some of the key parameters, we aim to investigate the behavior of dust particle and obtain their thermal history, which can be provided as background conditions for mineral condensation studies.

Pre-requisites: Calculus, fluid mechanics, programming skills highly desired
Keywords: High-performance computing, self-gravitating collapse, protostar formation, dust transport
Location: NTU & NTHU