PhD researcher · University of Nottingham
I study how intergalactic gas is heated, ionised and enriched, and how these processes shape quasar absorption spectra. By connecting simulations with observations, I use the Lyman-alpha forest and metal absorption to investigate this history and improve their interpretation as cosmological probes.
I am a PhD researcher at the University of Nottingham, working with Prof. James S. Bolton.
Nottingham, UK
Current base
2023–2027
Astrophysics PhD
IGM · Reionisation · Lyα forest
Research focus
01 · Research
Quasar absorption spectra preserve information about the physical state of cosmic gas. My research connects simulations with observations to understand how gas conditions shape these signatures, and what they can tell us about cosmic history.
01 · Thermal history
Hydrogen reionisation left temperature fluctuations in intergalactic gas. Their imprint on the large-scale Lyman-alpha forest power spectrum offers a way to investigate when and how reionisation occurred.
My contribution. I developed realistic mock spectra and an uncertainty framework for WEAVE-QSO. Under the adopted survey assumptions, the joint analysis of four redshift bins forecasts an approximately 4.5σ detection of the patchy-reionisation imprint. The forecast depends strongly on the largest scales, where continuum placement and high-column-density absorbers are particularly important.
Next questions. I aim to connect this imprint to physically motivated reionisation histories and assess which properties can be constrained. I will also explore whether combining the power spectrum with transmitted-flux measurements can reduce degeneracies, before applying the framework to WEAVE-QSO data as they become available.
02 · Enrichment & ionisation
Metal absorption carries information about both chemical enrichment and the radiation that ionises the gas. Separating these effects is essential for interpreting the absorption and understanding the history of intergalactic metals.
My contribution. I developed a simulation-based model of correlated Si III absorption in the Lyman-alpha forest power spectrum. This connects a source of contamination in forest measurements to the silicon abundance and ionisation state of the absorbing gas.
Current work and next questions. I am testing whether a common model can explain both the Si III signal and Si IV absorber statistics. I plan to investigate how gas density, self-shielding and halo environments affect this interpretation, and which enrichment–ionisation degeneracies the two observables can resolve.
I use simulation-derived spectra, forward modelling and statistical inference to test physical explanations against observations. Comparing complementary measurements helps establish which conclusions are robust and where a gas model needs to improve. Together, these studies also strengthen the physical modelling needed to use quasar absorption as a cosmological probe.
02 · Selected work
Lead-author work spanning survey forecasts, precision modelling and observational astronomy.
2026
Ke Ma et al. · Submitted to MNRAS · Lead author
Tests whether the thermal imprint of patchy reionisation can be detected under realistic WEAVE-QSO survey conditions.
2026
03 · Profile
I trained in theoretical physics at University College London, moved into observational astronomy as a research assistant at Tsinghua University, and now work at the intersection of simulations and spectra during my PhD at Nottingham.
That route has made crossing methodological boundaries a defining part of how I work: deriving a model, implementing the numerical analysis, testing it against simulations or data, and turning the result into a clear scientific argument.
Recent talk: contributed talk presented at COSMO-26, Leiden, August 2026.
2023–present
PhD in Astrophysics
University of Nottingham
Supervisor: James S. Bolton
2021–2023
Research Assistant in Astronomy
Tsinghua University
First-author ApJ research
2017–2021
MSci in Theoretical Physics
University College London
First Class Honours · 85/100
Wood Prize
Ranked 1st in second-year Physics, UCL Physics & Astronomy
Faculty Dean’s List
Top 5% graduating students, UCL Mathematical & Physical Sciences
CSC Research Excellence Scholarship
Competitive funding for PhD study at the University of Nottingham
04 · Connect
I welcome conversations about the thermal and enrichment history of cosmic gas, quasar absorption, and connecting simulations with spectroscopic observations.