Science Highlights

FHD + pyFHD science

FHD + pyFHD can be used for a wide range of science. Here we detail some of the most impactful uses of FHD + pyFHD in astrophysics and cosmology.

Li et al. 2019 — 2D power spectra of 40hrs of Murchison Widefield Array data

Cosmology

FHD + pyFHD have produced more publications on 21-cm power spectra upper limits than any other analysis suite. The combination of state-of-the-art techniques and ease of implementation and modification by all levels of researchers have resulted in a legacy of improving cosmological measurements.

First Season MWA EoR Power spectrum Results at Redshift 7
A. P. Beardsley, B. J. Hazelton, I. S. Sullivan, P. Carroll, N. Barry, M. Rahimi, B. Pindor, C. M. Trott, J. Line, Daniel C. Jacobs, M. F. Morales, J. C. Pober + many others
The first 21-cm upper limit by the Murchison Widefield Array which encoded over 5 years of blood, sweat, and tears.

Improving the Epoch of Reionization Power Spectrum Results from Murchison Widefield Array Season 1 Observations
N. Barry, M. Wilensky, C. M. Trott, B. Pindor, A. P. Beardsley, B. J. Hazelton, I. S. Sullivan, M. F. Morales, J. C. Pober, J. Line, B. Greig + many others
An improvement of an order of magnitude in the 21-cm power spectrum upper limit from the Murchison Widefield Array from analysis and RFI systematics.

First Season MWA Phase II Epoch of Reionization Power Spectrum Results at Redshift 7
W. Li, J. C. Pober, N. Barry, B. J. Hazelton, M. F. Morales, C. M. Trott, A. Lanman, M. Wilensky, I. Sullivan + many others
Further improvement using redundancy and better calibration techniques.

Byrne et al. 2022 — Stokes I diffuse emission map off the Galactic-plane covering over 10 hours in RA.

Catalogs

FHD + pyFHD have the ability to generate catalogs via the Holographic Mapping Function, which is an implementation of efficient A-projection using sparse matrices with facetless widefield polarized imaging, and is the only implementation of its kind. As such, FHD + pyFHD is on the forefront of catalog creation, mapping parts of the sky before large projects and in difficult regimes.

A high reliability survey of discrete Epoch of Reionization foreground sources in the MWA EoR0 field
P. A. Carroll, J. Line, M. F. Morales, N. Barry, A. P. Beardsley, B. J. Hazelton, D. C. Jacobs, J. C. Pober, I. S. Sullivan, R. L. Webster, + 54 others
Building a ~1400 square degree survey of one of the darkest spots in the sky down to 80mJy to EoR precision requirements.

A map of diffuse radio emission at 182 MHz to enhance epoch of reionization observations in the Southern hemisphere
R. Byrne, M. F. Morales, B. Hazelton, I. Sullivan, N. Barry, C. Lynch , J. L. B. Line, D. C. Jacobs
Creating a flux-complete polarized diffuse emission map over ~11,000 square degrees and highlighting the importance of diffuse flux as a function of the measurement space.

Barry & Chokshi 2022 — Power spectra error budget using simulations.

Simulations

FHD + pyFHD have full in-situ simulation infrastructure. These end-to-end simulations can be used to investigate sources of contamination, both external and internal, in the space of the measurement. These studies provide invaluable information as to the main causes of systematics. Some examples:

Calibration requirements for detecting the 21 cm epoch of reionization power spectrum and implications for the SKA
N. Barry, B. Hazelton, I. Sullivan, M. F. Morales, J. C. Pober
Spectral errors in calibration from incomplete foreground models and their effects on 21-cm science.

Fundamental Limitations on the Calibration of Redundant 21 cm Cosmology Instruments and Implications for HERA and the SKA
R. Byrne, M. F. Morales, B. Hazelton, W. Li, N. Barry, A. P. Beardsley, R. Joseph, J. C. Pober, I. Sullivan, C. Trott
Exploring spectral errors in redundant calibration and highlighting the pitfalls of solving for degenerate parameters.

Quantifying excess power from radio frequency interference in Epoch of Reionization measurements
M. J. Wilensky, N. Barry, M. F. Morales, B. J. Hazelton, R. Byrne
The RFI budget allowed in a 21-cm measurement using realistic sources.

The Role of the Instrumental Response in 21 cm Epoch of Reionization Power Spectrum Gridding Analyses
N. Barry & A. Chokshi
Incorporating analytic transforms in instrumental representations to reduce spectral error, and the unavoidable pitfalls of pixelation.