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20212026
most citedCosmic Multipoles in Galaxy Surveys II: Comparing Different Methods in Assessing the Cosmic Dipole

3 citations · 5 across the 6 of their papers we have counts for

collaborators

8 papers

astro-ph.CO2026

Wising up to CatWISE: using simulation-based inference to interpret the ecliptic bias and confirm the cosmic dipole excess

Oliver T. Oayda, Geraint F. Lewis

We apply Simulation-Based Inference ('SBI') to the cosmic dipole problem for the first time, measuring the distribution of quasar counts over the sky in the CatWISE2020 ('CatWISE')…

astro-ph.CO2026

Local environmental dependence on weak-lensing shear statistics

Sonia Akter Ema, Md Rasel Hossen, Krzysztof Bolejko +1

Despite the assumption that an ideal FLRW observer is not dependent on the local environment, observations are biased by the positions of the observers due to the matter correlatio…

astro-ph.CO20253 cited

Cosmic Multipoles in Galaxy Surveys II: Comparing Different Methods in Assessing the Cosmic Dipole

Vasudev Mittal, Oliver T. Oayda, Geraint F. Lewis

We present a comparative analysis of estimators and Bayesian methods for determining the number count dipole from cosmological surveys. The increase in discordance between the numb…

astro-ph.GA20251 cited

Streams and Shells Decoded: A Density-Driven Approach to Stellar Clustering in Galactic Halos with AstroLink

Viraj Ekanayaka, Smrithi Gireesh Babu, William H. Oliver +1

We present a novel method to differentiate stream-like and shell-like tidal remnants of stellar systems in galactic halos using the density-based approach of the clustering algorit…

astro-ph.CO2025

Revisiting The Cosmological Time Dilation of Distant Quasars: Influence of Source Properties and Evolution

Brendon J. Brewer, Geraint F. Lewis, Yuan Li

After decades of searching, cosmological time dilation was recently identified in the timescale of variability seen in distant quasars. Here, we expand on the previous analysis to…

astro-ph.CO2024

Cosmic Multipoles in Galaxy Surveys Part I: How Inferences Depend on Source Counts and Masks

Oliver T. Oayda, Vasudev Mittal, Geraint F. Lewis

We present a new approach to constructing and fitting dipoles and higher-order multipoles in synthetic galaxy samples over the sky. Within our Bayesian paradigm, we illustrate that…