Colloquium Abstract - Hazelton - 2025Oct03

October 3, 2025

11:00am Mountain

Bryna Hazelton (U Washington)

 

Enabling direct imaging radio telescopes and precision cosmology with pyFHD

 

Abstract

A new generation of sensitive radio observatories are being developed with ever increasing numbers of antennas to pursue cosmology, fast transients, astrophysics and near-earth space physics. The extreme data rates required for these telescopes has led to the development of direct imaging correlators that scale much more modestly than traditional correlators. However, standard radio astronomy tools cannot process data from direct imaging correlators, making it difficult to propose new direct imaging telescopes.

Fast Holographic Deconvolution (FHD) was developed in the 21cm cosmology community as an open source package that solves many of the analysis challenges encountered in that community. It has been used in several leading limits of the 21cm Epoch of Reionization power spectrum, demonstrating that it has the precision required for cosmology, as well as being used to make high-quality catalogs and polarized maps of galactic emission. FHD, originally written in IDL, shares a mathematical framework with direct imaging correlators, making it well placed to help address the data analysis challenges for such correlators. Recently, in a major development effort, the minimal set of FHD functionality required for a standard cosmology analysis was ported to python, resulting in the open source pyFHD package.

We are working to add critical functionality to the pyFHD python package that will enable deconvolution without using visibilities for direct imaging telescopes and for telescopes traditional correlators. We will test these developments with real world data from telescopes with both traditional (MWA) and direct imaging correlators (LWA EPIC correlator).

The functionality we will develop in pyFHD will enable the community to show the science performance of direct imaging radio telescopes with a full end-to-end pipeline, enabling future proposals for direct imaging telescopes. With these developments, the community will have a state-of-the-art reference implementation of the software needed to perform science without visibilities.


Local Host: Preshanth Jagannathan

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