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SKAO HI intensity mapping: blind foreground subtraction challenge
(University of the Western Cape, 2022)
Neutral Hydrogen Intensity Mapping (H I IM) surveys will be a powerful new probe of cosmology. However, strong astrophysical
foregrounds contaminate the signal and their coupling with instrumental systematics further ...
Constraining the reionization history using deep learning from 21-cm tomography with the Square Kilometre Array
(Oxford University Press, 2020)
Upcoming 21-cm surveys with the SKA1-LOW telescope will enable imaging of the neutral hydrogen distribution on cosmological scales in the early Universe. These surveys are expected to generate huge imaging data sets that ...
Evidence for cosmic acceleration with next-generation surveys: A model-independent approach
(Oxford University Press, 2020)
We quantify the evidence for cosmic acceleration using simulations of H(z) measurements from SKA- and Euclid-like surveys. We perform a non-parametric reconstruction of the Hubble parameters and its derivative to obtain ...
Statistical recovery of the BAO scale from multipoles of the beam-convolved 21 cm correlation function
(Royal Astronomical Society, 2021)
Despite being designed as an interferometer, theMeerKAT radio array (a Square Kilometre Array pathfinder) can also be used in
autocorrelation (‘single-dish’) mode, where each dish scans the sky independently. Operating ...
Considerations for optimizing the photometric classification of supernovae from the Rubin observatory
(IOP Publishing, 2022)
The Vera C. Rubin Observatory will increase the number of observed supernovae (SNe) by an order of
magnitude; however, it is impossible to spectroscopically confirm the class for all SNe discovered. Thus,
photometric ...
The Copernican principle in light of the latest cosmological data
(University of the Western Cape, 2022)
We pursue a program to confront observations with inhomogeneous extensions of the FLRW metric. The main idea is to test the Copernican principle (CP) rather than assuming it a priori. We consider the CDM model endowed with ...
Consequences of using a smooth cosmic distance in a lumpy Universe. I.
(American Physical Society, 2022)
How do we appropriately fit a model based on an idealised Friedmann-Lemaˆıtre Robertson-Walker
spacetime to observations made from a single location in a lumpy Universe? We address this question
for surveys that measure ...
Inferring halo masses with graph neural networks
(Institute of Physics, 2022)
Understanding the halo–galaxy connection is fundamental in order to improve our knowledge on the nature and
properties of dark matter. In this work, we build a model that infers the mass of a halo given the positions,
...
Ultralarge-scale approximations and galaxy clustering: Debiasing constraints on cosmological parameters
(Oxford University Press, 2022)
Upcoming galaxy surveys will allow us to probe the growth of the cosmic large-scale structure with improved sensitivity
compared to current missions, and will also map larger areas of the sky. This means that in addition ...
Antenna beam characterization for the global 21-cm experiment LEDA and its impact on signal model parameter reconstruction
(Oxford University Press, 2022)
Cosmic dawn, the onset of star formation in the early universe, can in principle be studied via the 21-cm transition of neutral hydrogen, for which a sky-averaged absorption signal, redshifted to MHz frequencies, is predicted ...