McGill Cosmic Dawn and Hydrogen Cosmology Group
Welcome to our research group!
We are a research group of cosmologists led by Prof. Adrian Liu in the Department of Physics and McGill Space Institute at McGill University. We work on the boundary between theory and observations. By using data from a new generation of radio telescopes, we seek to understand how the first stars and galaxies formed, as well as how they evolved into the galaxies today. Our long term goal is to map an unprecedentedly large volume of our observable Universe, which will also provide a window into fundamental cosmology.
Latest news
February 2025: Congratulations to soon-to-be-Dr. Bobby Pascua, who recently accepted a postdoc offer. Next year he will be in Ontario, as a joint prize Dunlap Institute Fellow, University of Toronto Arts & Science Fellow, and a Perimeter Institute Fellow!
February 2025: Congratulations to soon-to-be-Dr. Hannah Fronenberg, who recently accepted a postdoc offer. Next year she will be a prize Kavli Institute for Cosmological Physics (KICP) Fellow at the University of Chicago!
February 2025: Great job Franco Del Balso! New on the arXiv is our proposal to combine machine learning and 21cm cosmology to place constraints on the geometry and expansion rate of our Universe! https://arxiv.org/abs/2502.02638
Archived news
December 2023: Congratulations to Dr. Lisa McBride, who successfully defended his PhD thesis! Lisa is off to postdoc position with Dr. Marian Douspis at the Université Paris-Saclay. Good luck Lisa!
November 2023: Congratulations to Hannah Fronenberg for winning the national Mitacs Award for Outstanding Innovation -- International! Check out the slick Mitacs award video.
September 2023: A pair of papers by Hannah Fronenberg, taking a detailed look at using intensity maps to cancel out the low-redshift contributions to CMB lensing. The first one (https://arxiv.org/abs/2309.06477) talks about how we can use it to constrain cosmology (e.g., neutrino mass, weird deviations from LCDM), while the second one talks about a clever way to measure the baryon acoustic oscillations at z ~ 5 (https://arxiv.org/abs/2309.07215).
August 2023: Another one! A follow-on from Sam Gagnon-Hartman's previous paper (https://arxiv.org/abs/2102.08382), led this time by Jacob Kennedy. Jacob finds that if we use a machine-learning-enhanced 21cm map, we can learn something about high redshift galaxy populations. Check it out here: https://arxiv.org/abs/2308.09740Â
August 2023: New paper led by Lisa McBride, taking a rigorous look at whether intensity mapping autocorrelations can be inferred from cross correlations. Check it out here: https://arxiv.org/abs/2308.00749Â
June 2023: Congratulations to our BSc graduates, in particular our now-former undergraduate researchers Hugo Baraër (travelling the world in a gap-year tour), Aidan Lewandowski (now an intern at Herzberg Institute of Astrophysics), Yael Demers (continuing as a researcher in this group for the summer)!
May 2023: Congratulations to Dr. Michael Pagano not only for finishing his degree, but doing so in style! Michael has been selected as one of the recipients of the D.W. Ambridge Prize at Convocation, awarded to two of the most outstanding students graduating in the Natural Sciences. Congratulations Michael!
April 2023: April Fools Day! For some light-hearted fun, check out the joke paper that Lisa McBride and Michael Pagano posted: https://arxiv.org/abs/2303.17637Â
March 2023: Our team (especially Jordan Mirocha, Adélie Gorce, Saurabh Singh, Lisa McBride, and Bobby Pascua) played a crucial role in the latest upper limits on the 21cm power spectrum from HERA that have just been published. These are the most sensitive limits to date, and (among other interesting results) provide tantalizing evidence that the first-generation galaxies differ from today's galaxies in their X-ray luminosity.
Nov 30, 2022: Congratulations to Dr. Michael Pagano, who successfully defended his PhD thesis! Michael is off to join Prof. Andrei Mesinger (Scuola Normale Superiore) and Prof. Carmelo Evoli (Gran Sasso Science Institute) as a postdoc next year. For now he not only wraps up his PhD work but also has had a busy time submitting two new papers, one on Bayesian analyses for the REACH global signal experiment (https://arxiv.org/abs/2211.10448) and one on using machine learning to in-paint of data gaps (https://arxiv.org/abs/2210.14927).
Oct 2022: New paper (led by Dr. Adélie Gorce) about window functions for upcoming HERA measurements. These are crucial for making sure we understand what we're seeing! Check it out here: https://arxiv.org/abs/2210.03721Â
May 2022: Congratulations to our BSc graduates, in particular our now-former undergraduate researchers Joëlle-Marie Bégin (heading off to do a PhD in Physics at Princeton), Jade Ducharme (PhD in Physics at Brown), Alex Laroche (MSc in Astronomy at Toronto), Jasmine Parsons (PhD in Astrophysics at Princeton), and Kevin Sohn (MSc in Physics at Imperial College)!
May 27, 2022: Check out our new paper (led by Dr. Jordan Mirocha) on how near-infrared intensity mapping experiments (like SPHEREx) might be able to detect signatures of reionization feedback! Check it out here: https://arxiv.org/abs/2205.14168
Dec 14, 2021: And in quick succession, undergrad researcher Joëlle-Marie Bégin and Trottier Astrophysics Fellow Dr. Adélie Gorce have pushed out a paper on Joint constraints on reionization: a framework for combining the global 21cm signal and the kinetic Sunyaev-Zel'dovich effect. Check it out here: https://arxiv.org/abs/2112.06933
Dec 13, 2021: Check out the latest paper (https://arxiv.org/abs/2112.06407) by undergrad researcher Jasmine Parsons, who looked at Probing Population III IMFs with He II/Hα Intensity Mapping with collaborators at JPL!Â
Sept 10, 2021: Congratulations to our undergraduate researcher Jade Ducharme being one of the winners for the Department of Physics and McGill Space Institute's Best Talk at the 2021 Summer Research Showcase!
Sept 7, 2021: Congratulations to PhD student Michael Pagano for getting his latest paper, Lyman Alpha Emitters and the 21cm Poster Spectrum as Probes of Density-Ionization Correlation in the Epoch of Reionization, accepted for publication in MNRAS! Check out an advanced version here: https://arxiv.org/abs/2105.03434