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Improved upper limits on the 21 cm signal power spectrum of neutral hydrogen at z ≈ 9.1 from LOFAR
A new upper limit on the 21-cm signal power spectrum at a redshift of $z \approx 9.1$ is presented, based on 141 hours of data obtained with the Low-Frequency Array (LOFAR). The analysis includesExpand
21 cm signal from cosmic dawn: Imprints of spin temperature fluctuations and peculiar velocities
The 21 cm brightness temperature $\delta T_{\rm b}$ fluctuations from reionization promise to provide information on the physical processes during that epoch. We present a formalism for generatingExpand
Optimal identification of H ii regions during reionization in 21-cm observations
The ability of the future low-frequency component of the Square Kilometre Array radio telescope to produce tomographic images of the redshifted 21-cm signal will enable direct studies of the evolutExpand
Constraining the intergalactic medium at z ≈ 9.1 using LOFAR Epoch of Reionization observations
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 by the LOFAR radio telescopeExpand
21 cm signal from cosmic dawn - II. Imprints of the light-cone effects
Details of various unknown physical processes during the cosmic dawn and the epoch of reionization can be extracted from observations of the redshifted 21-cm signal. These observations, however, willExpand
Position-dependent power spectra of the 21-cm signal from the epoch of reionization
The 21-cm signal from the epoch of reionization is non-Gaussian. Current radio telescopes are focused on detecting the 21-cm power spectrum, but in the future the Square Kilometre Array isExpand
Interpreting LOFAR 21-cm signal upper limits at z ≈ 9.1 in the context of high-z galaxy and reionization observations
Using the latest upper limits on the 21-cm power spectrum at $z\approx9.1$ from the Low Frequency Array (LOFAR), we explore regions of parameter space which are inconsistent with the data. We useExpand
Measuring the reionization 21 cm fluctuations using clustering wedges
One of the main challenges in probing the reionization epoch using the redshifted 21 cm line is that the magnitude of the signal is several orders smaller than the astrophysical foregrounds. One ofExpand
Tight constraints on the excess radio background at z = 9.1 from LOFAR
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 radio background isExpand
Prediction of the 21-cm signal from reionization: comparison between 3D and 1D radiative transfer schemes
Three-dimensional radiative transfer simulations of the epoch of reionization can produce realistic results, but are computationally expensive. On the other hand, simulations relying on one-dimensiExpand