550 citations · 2.5k across the 71 of their papers we have counts for
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Measuring the topology of reionization with Betti numbers
Sambit K. Giri, Garrelt Mellema
The distribution of ionised hydrogen during the epoch of reionization (EoR) has a complex morphology. We propose to measure the three-dimensional topology of ionised regions using…
Redshift-space distortions in simulations of the 21-cm signal from the cosmic dawn
Hannah E. Ross, Sambit K. Giri, Keri L. Dixon +3
The 21-cm signal from the Cosmic Dawn (CD) is likely to contain large fluctuations, with the most extreme astrophysical models on the verge of being ruled out by observations from…
Comparing Foreground Removal Techniques for Recovery of the LOFAR-EoR 21cm Power Spectrum
Ian Hothi, Emma Chapman, Jonathan R. Pritchard +10
We compare various foreground removal techniques that are being utilised to remove bright foregrounds in various experiments aiming to detect the redshifted 21cm signal of neutral…
A halo model approach for the 21-cm power spectrum at cosmic dawn
Aurel Schneider, Sambit K. Giri, Jordan Mirocha
Prior to the epoch of reionisation, the 21-cm signal of the cosmic dawn is dominated by the Lyman- coupling and gas temperature fluctuations caused by the first sources of radia…
Interpreting LOFAR 21-cm signal upper limits at z~9.1 in the context of high-z galaxy and reionisation observations
Bradley Greig, Andrei Mesinger, Léon V. E. Koopmans +11
Using the latest upper limits on the 21-cm power spectrum at from the Low Frequency Array (LOFAR), we explore regions of parameter space which are inconsistent with t…
Tight Constraints on the Excess Radio Background at from LOFAR
R. Mondal, A. Fialkov, C. Fling +13
The ARCADE2 and LWA1 experiments have claimed an excess over the Cosmic Microwave Background (CMB) at low radio frequencies. If the cosmological high-redshift contribution to this…
Improved upper limits on the 21-cm signal power spectrum of neutral hydrogen at from LOFAR
F. G. Mertens, M. Mevius, L. V. E Koopmans +23
A new upper limit on the 21-cm signal power spectrum at a redshift of is presented, based on 141 hours of data obtained with the Low-Frequency Array (LOFAR). The an…
Constraining the intergalactic medium at 9.1 using LOFAR Epoch of Reionization observations
R. Ghara, S. K. Giri, G. Mellema +19
We derive constraints on the thermal and ionization states of the intergalactic medium (IGM) at redshift 9.1 using new upper limits on the 21-cm power spectrum measured b…