相关论文: The EDGES Analysis Pipeline: Description and Valid…
Weakly interacting cold dark matter (CDM) particles, which are otherwise extremely successful in explaining various cosmological observations, exhibit a number of problems on small scales. One possible way of solving these problems is to…
In the standard cosmology, it is believed that there are two relatively weak and distinct band-limited absorption features, with the first absorption minima near 20 MHz ($z\sim70$) and the other minima at higher frequencies between 50-110…
Radiometer experiments to detect 21-cm Hydrogen line emission from the Cosmic Dawn and Epoch of Reionization rely upon precise absolute calibration. During calibration, noise generated by amplifiers within the radiometer receiver must be…
The astrophysics of cosmic dawn, when star formation commenced in the first collapsed objects, is predicted to be revealed as spectral and spatial signatures in the cosmic radio background at long wavelengths. The sky-averaged redshifted…
Recent results from the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) show an anomalous spectral feature at redshifts $z\sim 15-20$ in its 21-cm absorption signal. This deviation from cosmological predictions can…
The dark ages 21-cm signal is a promising probe of the currently unobserved infant universe between the formation of the Cosmic Microwave Background around $z \approx 1100$ and the first galaxies around $z\approx 30$. A detection of the…
While the $\mathbb{Z}_3$ symmetric dark matter models have shown tremendous prospects in addressing a number of (astro-)particle physics problems, they can leave interesting imprints on cosmological observations as well. We consider two…
The redshifted 21-cm emission by neutral hydrogen offers a unique tool for mapping structure formation in the early universe in three dimensions. Here we provide the first detailed calculation of the 21-cm emission signal during and after…
The Electromagnetically Isolated Global Signal Estimation Platform (EIGSEP) is a new instrument designed to measure the global 21-cm signal from Cosmic Dawn and the Epoch of Reionization, redshifted to frequencies below 250 MHz. To reduce…
Calibration precision is currently a limiting systematic in 21 cm cosmology experiments. While there are innumerable calibration approaches, most can be categorized as either `sky-based,' relying on an extremely accurate model of…
We describe how the high-redshift 21-cm background can be used to improve both our understanding of the fundamental cosmological parameters of our Universe and exotic processes originating in the dark sector. The 21-cm background emerging…
The EDGES Collaboration has reported an anomalously strong 21cm absorption feature corresponding to the era of first star formation, which may indirectly betray the influence of dark matter during this epoch. We demonstrate that, by virtue…
Development of the hardware, data analysis, and simulation techniques for large compact radio arrays dedicated to mapping the 21 cm line of neutral hydrogen gas has proven to be more difficult than imagined twenty years ago when such…
Upcoming measurements of the 21-cm line of neutral hydrogen will open a new observational window into the early stages of structure growth, providing a unique opportunity for probing large-scale cosmological signatures using the small-scale…
Imaging the Universe during the first hundreds of millions of years remains one of the exciting challenges facing modern cosmology. Observations of the redshifted 21 cm line of atomic hydrogen offer the potential of opening a new window…
We demonstrate the effectiveness of a Bayesian evidence-based analysis for diagnosing and disentangling the sky-averaged 21-cm signal from instrumental systematic effects. As a case study, we consider a simulated REACH pipeline with an…
Recently the EDGES collaboration reported an anomalous absorption signal in the sky-averaged 21-cm spectrum around $z=17$. Such a signal may be understood as an indication for an unexpected cooling of the hydrogen gas during or prior to the…
We present a differentiable, end-to-end Bayesian forward modeling framework for line intensity mapping cosmology experiments, with a specific focus on low-frequency radio telescopes targeting the redshifted 21 cm line from neutral hydrogen…
The Epoch of Reionization (EoR) and Cosmic Dawn (CD) are pivotal stages during the first billion years of the universe, exerting a significant influence on the development of cosmic structure. The detection of the redshifted 21-cm signal…
A recent observation by the EDGES collaboration shows a strong absorption signal in the global 21-cm spectrum from around a redshift of $z = 17$. This absorption is stronger than the maximum prediction by existing models and indicates that…