Cosmic Dawn Lab is a research group spread across the Institute of Astronomy, Kavli Institute for Cosmology and Cavendish Laboratory at the University of Cambridge focused on exploring the first few billion years of the Universe.

The research spans from the cosmic Dark Ages to present day including topics such as: 21-cm line of neutral hydrogen, intensity mapping of other molecular and atomic lines, structure formation, nature of dark matter, transient phenomena such as Fast Radio Bursts, and low frequency radio observations and instrumentation.

Principal Investigator

Anastasia Fialkov

Anastasia Fialkov is a Professor of Astrophysics and Cosmology at the Institute of Astronomy and the principle investigator of the Cosmic Dawn Lab research group. Her research interests spans a broad range of topics, as described above.

Read more here

Post-docs

Boyuan Liu

Boyuan Liu is a postdoc working on population synthesis of binary black hole mergers and X-ray binaries from the first stars, the effects of primordial black holes on early star formation, and the synergy between 21-cm and gravitational wave observations of Cosmic Dawn. He gained his PhD in 2022 at the University of Texas at Austin, where he developed semi-analytical models and cosmological simulations of the first generation of stars, black holes, and galaxies at Cosmic Dawn, to evaluate their observational signatures and implications on dark matter physics.

See personal website

Affiliated post-docs

Harry Bevins

Harry Bevins is a Junior Research Fellow in the Kavli Institute for Cosmology Cambridge and collaborates with the group on statistical methods for 21cm Cosmology and the interpretation of current observations. Harry has worked on the development of machine learning enhanced Bayesian pipelines for 21cm Cosmology and has developed state-of-the-art emulators for the outputs of the semi-numerical code 21cmSPACE.

See personal website

PhD students

Tibor Dome

Tibor Dome is a 4th year PhD student with a primary focus on numerical cosmology and computational astrophysics. He studies the cosmological/astrophysical manifestations of dark matter, which continue to challenge the scientific community. However, these manifestations are degenerate with baryonic physics due to our lack of knowledge thereof, blurring the distinct signatures of dark matter and weakening the constraints. His PhD work thus investigates galaxy formation in promising dark matter models such as fuzzy dark matter (FDM), consisting of ultra-light axion-like particles (ALPs) with masses \(m_a \sim 10^{-21}\text{ eV}\), predicted by both string theory and quantum field theory. By virtue of being bosons, these particles are exempt from fermionic restrictions such as the Tremaine-Gunn bound and have gained significant attention as potential solutions to some of the small-scale issues in ΛCDM.

Thomas Gessey-Jones

Thomas Gessey-Jones is a 4th year PhD student working on the interplay between the first stars and the 21-cm cosmology, with a particular focus on what ongoing and future 21-cm signal experiments can tell us about the properties of this enigmatic stellar population. He is a member of the HERA and REACH collaborations and is co-supervised by Eloy de Lera Acedo and Will Handley, with the latter of whom he also researches Bayesian statistical methods, including simulation-based inference.

Alex Tocher

Alex is a 3rd year PhD student working on simulations of early universe star formation under fuzzy dark matter (FDM) conditions to look for unique effects of the (FDM) dynamics on the star forming gas, and to use these simulations to inform 21cm predictions under FDM conditions. Alex has worked to combine the Population III star formation models and the FDM solver within the large cosmological hydrodynamics code AREPO, which has allowed us to demonstrate clear differences in star formation processes within low mass FDM halos when compared to similar CDM halos.

Simon Pochinda

Simon is a 3rd year PhD student affiliated with Cavendish Astrophysics. He has worked on producing joint constraints on 21cmSPACE models with multi-wavelength data from 21-cm experiments, and observations of the X-ray and radio backgrounds. Simon currently works on adapting generative models for super-resolution of large simulated 3D cosmological volumes.

Emma Shen

Emma Shen is a 3rd year PhD student primarily working on data analysis and modelling of foregrounds in global 21-cm experiments (e.g. REACH). They have been studying chromatic ionospheric effects and polarised foregrounds, as well as the FlexKnot signal model. They are also looking to study the contribution of mini-quasars to the X-ray background. The PhD project is jointly funded by Cambridge Trust and the Ministry of Education in Taiwan.

Jiten Dhandha

Jiten Dhandha is a 2nd year PhD student working on observational synergies between JWST and 21-cm experiments. He has previously worked on 21-cm signal modelling in the context of CMB spectral distortions, and also star-formation in molecular clouds during his Masters at the University of Manchester. He primarily works on theory modelling using 21cmSPACE as part of the REACH collaboration, focusing on star-formation in the Early Universe.

See personal website

Saswata Dasgupta

Saswata Dasgupta is a 1st year PhD student working on the effect of the stochastic nature of X-ray Binaries on the 21-cm signal from Cosmic Dawn and the Epoch of Reionization. He is also a part of the REACH collaboration, working on the calibration pipeline, looking for optimal bands for receiver calibration. During his Master’s in the Indian Institute of Technology, Indore, he has worked on Image analysis of 21-cm fields from the CD-EoR era using synthetic SKA observations.

Part III / Masters students

Daniel Kessler

Daniel Kessler is a MASt student studying the effects of early stars’ chemical homogeneity on reionization and the 21-cm signal. This work involves using the semi-numerical code 21cmSPACE to simulate early star formation and the subsequent ionization of neutral hydrogen, which absorbs and emits 21cm radiation to varying degrees throughout cosmic history.

Past members

Post-docs

Nina Sartorio (PDRA, 2019 – 2022), currently FWO junior postdoctoral fellow, University of Ghent.

PhD students

Stefan Heimersheim (2019 – 2023), currently at Apollo Research.
Harry Bevins (2019 – 2023), currently a KICC Fellow.

Part III / Master students

Nora Gavrea (2023 – 2024) at IoA.
Rachel Incley (2023 – 2024) at IoA.
Zhihan Guo (2023 – 2024) at IoA.
Rumail Azhar (2022 – 2023) at IoA.
Adithya Nandakumar (2022 – 2023) at IoA.
Clark Huang (2021 – 2022) at Cavendish, co-advised with E. de Lera Acedo.
Vasundhara Prasad (2021 – 2022) at IoA.
Edmund Ross (2021 – 2022) at IoA.
Irene Abril Cabezas (2021 – 2022, +summer) at IoA.
Alex Tocher (2020 – 2021, +summer) at IoA.
Pan You Qi Yuki (2020 – 2021) at Cavendish, co-advised with E. de Lera Acedo.
Emma Shen (2019 – 2020) at Cavendish, co-advised with E. de Lera Acedo and W. Handley.