中文
相关论文

相关论文: Effective bias expansion for circumventing 21 cm f…

200 篇论文

The Epoch of Reionization (EoR)---when neutral hydrogen in the intergalactic medium was systematically ionized---is a period in our Universe's history that is currently poorly understood. However, a key prediction of most models is a…

宇宙学与河外天体物理 · 物理学 2021-05-25 Michael Pagano , Adrian Liu

The redshifted 21 cm line of cosmic atomic hydrogen is one of the most auspicious tools in deciphering the early Universe. Recovering this signal remains an ongoing problem for cosmologists in the field, with the signal being hidden behind…

宇宙学与河外天体物理 · 物理学 2024-09-18 Joe H. N. Pattison , Jean Cavillot , Harry T. J. Bevins , Dominic J. Anstey , Eloy de Lera Acedo

Experiments designed to measure the redshifted 21~cm line from the Epoch of Reionization (EoR) are challenged by strong astrophysical foreground contamination, ionospheric distortions, complex instrumental response and other different types…

The power spectrum of redshifted 21 cm emission brightness temperature fluctuations is a powerful probe of the Epoch of Reionization (EoR). However, bright foreground emission presents a significant impediment to its unbiased recovery from…

宇宙学与河外天体物理 · 物理学 2019-07-31 Peter H. Sims , Jonathan C. Pober

A detection of the 21 cm signal can provide a unique window of opportunity for uncovering complex astrophysical phenomena at the epoch of reionization and placing constraints on cosmology at high redshifts, which are usually elusive to…

宇宙学与河外天体物理 · 物理学 2024-06-21 Danial Baradaran , Boryana Hadzhiyska , Martin J. White , Noah Sailer

21cm-galaxy cross-correlation will play a key role in confirming the cosmological 21cm signal. We investigate which survey configurations detect the 21cm-LAE cross-correlation signal, and assess its ability to distinguish reionisation…

宇宙学与河外天体物理 · 物理学 2026-03-18 Anne Hutter , Caroline Heneka

The future of precision cosmology could benefit from cross-correlations between intensity maps of unresolved neutral hydrogen (HI) and more conventional optical galaxy surveys. A major challenge that needs to be overcome is removing the…

宇宙学与河外天体物理 · 物理学 2019-07-17 Steven Cunnington , Laura Wolz , Alkistis Pourtsidou , David Bacon

Observations with radio arrays that target the 21-cm signal originating from the early Universe suffer from a variety of systematic effects. An important class of these are reflections and spurious couplings between antennas. We apply a…

We present new constraints on the 21cm Epoch of Reionization (EoR) power spectrum derived from 3 months of observing with a 32-antenna, dual-polarization deployment of the Donald C. Backer Precision Array for Probing the Epoch of…

Intensity mapping -- the large-scale mapping of selected spectral lines without resolving individual sources -- is quickly emerging as an efficient way to conduct large cosmological surveys. Multiple surveys covering a variety of lines…

宇宙学与河外天体物理 · 物理学 2025-01-22 Hannah Fronenberg , Adrian Liu

Observing the neutral hydrogen distribution across the Universe via redshifted 21cm line intensity mapping constitutes a powerful probe for cosmology. However, the redshifted 21cm signal is obscured by the foreground emission from our…

The deep learning technique has been employed in removing foreground contaminants from 21 cm intensity mapping, but its effectiveness is limited by the large dynamic range of the foreground amplitude. In this study, we develop a novel…

宇宙学与河外天体物理 · 物理学 2024-03-13 Feng Shi , Haoxiang Chang , Le Zhang , Huanyuan Shan , Jiajun Zhang , Suiping Zhou , Ming Jiang , Zitong Wang

21cm radiation from neutral hydrogen serves as a direct probe of the Epoch of Reionization. However, both its detection and physical interpretation are severely hindered by contamination from astrophysical foreground emission and…

宇宙学与河外天体物理 · 物理学 2026-05-07 Anirban Chakraborty , Kwanit Gangopadhyay , Arka Banerjee , Tirthankar Roy Choudhury

The amplitude of redshifted 21 cm fluctuations during the Epoch of Reionization (EoR) is expected to show a distinctive "rise and fall" behavior with decreasing redshift as reionization proceeds. On large scales (k <~ 0.1 Mpc^{-1}) this can…

宇宙学与河外天体物理 · 物理学 2018-11-06 Angus Beane , Adam Lidz

Observations of the 21 cm signal face significant challenges due to bright astrophysical foregrounds that are several orders of magnitude higher than the brightness of the hydrogen line, along with various systematics. Successful 21 cm…

宇宙学与河外天体物理 · 物理学 2024-12-11 Chuneeta D. Nunhokee , Dev Null , Cathryn M. Trott , Christopher H. Jordan , Jack B. Line , Randall Wayth , Nichole Barry

One of the aims of the Low Frequency Array (LOFAR) Epoch of Reionization (EoR) project is to measure the power spectrum of variations in the intensity of redshifted 21-cm radiation from the EoR. The sensitivity with which this power…

The post-reionization $(z \le 6)$ neutral hydrogen (HI) 21-cm intensity mapping signal holds the potential to probe the large scale structures, study the expansion history and constrain various cosmological parameters. Here we apply the…

The precise form of the foregrounds for sky-averaged measurements of the 21-cm line during and before the epoch of reionization is unknown. We suggest that the level of complexity in the foreground models used to fit global 21-cm data…

宇宙学与河外天体物理 · 物理学 2015-02-26 Geraint Harker

Neutral hydrogen (HI) serves as a crucial probe for the Cosmic Dawn and the Epoch of Reionization (EoR). Actual observations of the 21-cm signal often encounter challenges such as thermal noise and various systematic effects. To overcome…

A number of experiments are currently working towards a measurement of the 21 cm signal from the Epoch of Reionization. Whether or not these experiments deliver a detection of cosmological emission, their limited sensitivity will prevent…