Angular power spectra of 610 MHz radio halos show excess power-law fluctuations only in Abell 2744, requiring multiplicative C_ℓ ∝ ℓ^{-3} structure atop an exponential profile and consistent with ICM turbulence.
A simulation calibrated limit on the HI power spectrum from the GMRT Epoch of Reionization experiment
2 Pith papers cite this work. Polarity classification is still indexing.
abstract
The GMRT Epoch of Reionization (EoR) experiment is an ongoing effort to measure the power spectrum from neutral hydrogen at high redshift. We have previously reported an upper limit of (70 mK)^2 at wavenumbers of k=0.65 h/Mpc using a basic piecewise-linear foreground subtraction. In this paper we explore the use of a singular value decomposition to remove foregrounds with fewer assumptions about the foreground structure. Using this method we also quantify, for the first time, the signal loss due to the foreground filter and present new power spectra adjusted for this loss, providing a revised measurement of a 2-sigma upper limit at (248 mK)^2 for k=0.50 h/Mpc. While this revised limit is larger than previously reported, we believe it to be more robust and still represents the best current constraints on reionization at z=8.6.
fields
astro-ph.CO 2years
2026 2representative citing papers
21cmEMUv3 emulates the cylindrical 21cm power spectrum via score-based diffusion and six other 21cmFAST observables via LSTM networks at sub-percent accuracy, then uses the emulator to infer a lower limit on soft-band X-ray luminosity from HERA data.
citing papers explorer
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Intensity fluctuations of radio halo in galaxy cluster: Insights from power spectrum estimation
Angular power spectra of 610 MHz radio halos show excess power-law fluctuations only in Abell 2744, requiring multiplicative C_ℓ ∝ ℓ^{-3} structure atop an exponential profile and consistent with ICM turbulence.
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21cmEMUv3: a hybrid diffusion-LSTM emulator of 21cmFAST summary observables
21cmEMUv3 emulates the cylindrical 21cm power spectrum via score-based diffusion and six other 21cmFAST observables via LSTM networks at sub-percent accuracy, then uses the emulator to infer a lower limit on soft-band X-ray luminosity from HERA data.