Wavelet-scattering Signatures of Fuzzy Dark Matter in Simulated 21 cm Brightness–Temperature Maps
Year: 2026
Type: article
Abstract: We study the effect of fuzzy dark matter (FDM) on the multiscale morphology of simulated redshifted 21 cm maps during Cosmic Dawn and the Epoch of Reionization. Using FDM-modified 21cmFAST light cones, we apply the two-dimensional wavelet scattering transform (WST) to matched 2 MHz map products. The first-order coefficients S 1 ( j ) summarize wavelet-band amplitudes, while the normalized second-order ratio R = S 2 / S 1 ( j 1 ) measures ordered cross-scale modulation. FDM shifts and reshapes both summaries through delayed halo and source formation. We compare a two-dimensional power spectrum (PS), WST, and their combination on the same transferred and noisy maps. In this controlled local Fisher analysis, PS+WST reduces the marginalized errors on the FDM mass, effective X-ray emissivity normalization, and ionizing efficiency by approximately a factor of 1.8 relative to the matched two-dimensional PS baseline, although the dominant mass-heating degeneracy remains. An idealized three-wedge test shows that R is less reshaped at the coefficient level than S 1 . The covariance includes thermal noise conditional on one fiducial light cone but not cosmic variance or foreground residuals; the results are, therefore, relative information comparisons, not survey forecasts or a demonstration of superiority over a full three-dimensional PS analysis.
Source: The Astrophysical Journal
Authors: Hayato Shimabukuro, Shihang Liu, Bohua Li
Institutions: Yunnan University, Nagoya University, Beijing Normal University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
OpenAlex ID: W4416936445