59 citations · 243 across the 23 of their papers we have counts for
10 papers · 1 filter
The impact of lunar topography on the 21-cm power spectrum for grid-based arrays : Insights for the Dark-ages EXplorer (DEX)
S. Ghosh, L. V. E. Koopmans, C. Brinkerink +17
The Dark Ages (DA) provides a crucial window into the physics of the infant Universe, with the 21-cm signal offering the only direct probe for mapping out the three-dimensional dis…
Improved upper limits on the 21-cm signal power spectrum at and from an optimal field observed with NenuFAR
S. Munshi, F. G. Mertens, J. K. Chege +19
We report the deepest upper limits to date on the power spectrum of the 21-cm signal during the Cosmic Dawn (redshifts: ), using four nights of observations with NenuFAR. The…
Mitigating incoherent excess variance in high-redshift 21 cm observations with multi-output cross-Gaussian process regression
S. Munshi, L. V. E. Koopmans, F. G. Mertens +8
Systematic effects that limit the achievable sensitivity of current low-frequency radio telescopes to the 21 cm signal are among the foremost challenges in observational 21 cm cosm…
Constraints on the state of the IGM at using redshifted 21-cm observations with LOFAR
R. Ghara, S. Zaroubi, B. Ciardi +21
The power spectra of the redshifted 21-cm signal from the Epoch of Reionization (EoR) contain information about the ionization and thermal states of the intergalactic medium (IGM),…
First upper limits on the 21-cm signal power spectrum of neutral hydrogen at from the LOFAR 3C196 field
E. Ceccotti, A. R. Offringa, F. G. Mertens +16
The redshifted 21-cm signal of neutral hydrogen from the Epoch of Reionization (EoR) can potentially be detected using low-frequency radio instruments such as the Low-Frequency Arr…
Deeper multi-redshift upper limits on the Epoch of Reionization 21-cm signal power spectrum from LOFAR between z=8.3 and z=10.1
F. G. Mertens, M. Mevius, L. V. E. Koopmans +20
We present new upper limits on the 21-cm signal power spectrum from the Epoch of Reionization (EoR), at redshifts , based on reprocessed obse…
The impact of diffuse Galactic emission on direction-independent gain calibration in high-redshift 21 cm observations
C. Höfer, L. V. E. Koopmans, S. A. Brackenhoff +7
This study examines the impact of diffuse Galactic emission (DGE) on sky-based direction-independent (DI) gain calibration using realistic forward simulations of Low-Frequency Arra…
Robust direction-dependent gain-calibration of beam-modelling errors far from the target field
S. A. Brackenhoff, A. R. Offringa, M. Mevius +8
Many astronomical questions require deep, wide-field observations at low radio frequencies. Phased arrays like LOFAR and SKA-low are designed for this, but have inherently unstable…
Square Kilometre Array Science Data Challenge 3a: foreground removal for an EoR experiment
A. Bonaldi, P. Hartley, R. Braun +179
We present and analyse the results of the Science data challenge 3a (SDC3a, https://sdc3.skao.int/challenges/foregrounds), an EoR foreground-removal community-wide exercise organis…
Spectral modelling of Cygnus A between 110 and 250 MHz. Impact on the LOFAR 21-cm signal power spectrum
E. Ceccotti, A. R. Offringa, L. V. E. Koopmans +15
Studying the redshifted 21-cm signal from the the neutral hydrogen during the Epoch of Reionization and Cosmic Dawn is fundamental for understanding the physics of the early univer…