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Line-intensity mapping (LIM) traces the large-scale distribution of matter by measuring fluctuations in aggregate line emission from unresolved galaxies and the intergalactic medium, providing a powerful probe of both astrophysics and…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-03 Marina S. Cagliari , Zucheng Gao , Azadeh Moradinezhad Dizgah

The upcoming Square Kilometre Array Observatory (SKAO) will produce images of neutral hydrogen distribution during the epoch of reionization by observing the corresponding 21-cm signal. However, the 21-cm signal will be subject to…

Instrumentation and Methods for Astrophysics · Physics 2024-02-29 Michele Bianco , Sambit. K. Giri , David Prelogović , Tianyue Chen , Florent G. Mertens , Emma Tolley , Andrei Mesinger , Jean-Paul Kneib

We explore a novel analysis framework for parameter inference with large-scale CMB polarization data. Our method uses simulation-based inference combined with the needlet internal linear combination (NILC) algorithm and…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-19 Adriaan J. Duivenvoorden , Kristen Surrao , Adrian E. Bayer , Alexandre E. Adler , Nadia Dachlythra , Susanna Azzoni , J. Colin Hill

Observations of the redshifted 21-cm signal emitted by neutral hydrogen represent a promising probe of large-scale structure in the universe. However, cosmological 21-cm signal is challenging to observe due to astrophysical foregrounds…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Haochen Wang , Juan Mena-Parra , Tianyue Chen , Kiyoshi Masui

We present the first application of a new foreground removal pipeline to the current leading HI intensity mapping dataset, obtained by the Green Bank Telescope (GBT). We study the 15hr and 1hr field data of the GBT observations previously…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-18 L. Wolz , C. Blake , F. B. Abdalla , C. M. Anderson , T. -C. Chang , Y. -C. Li , K. W. Masui , E. Switzer , U. -L. Pen , T. C. Voytek , J. Yadav

We forecast constraints on neutral hydrogen (HI) and cosmological parameters using near-term intensity mapping surveys with instruments such as BINGO, MeerKAT, and the SKA, and Stage III and IV optical galaxy surveys. If foregrounds and…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-25 Alkistis Pourtsidou , David Bacon , Robert Crittenden

The observations of the redshifted 21-cm signal from neutral hydrogen are a promising probe for understanding the Cosmic Dawn and the Epoch of Reionisation (EoR). One of the primary obstacles to the statistical detection of the Cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-22 Eeshan Beohar , Abhirup Datta , Anshuman Tripathi , Samit Kumar Pal , Rashmi Sagar

The exceptional sensitivity of the SKA will allow observations of the Cosmic Dawn and Epoch of Reionization (CD/EoR) in unprecedented detail, both spectrally and spatially. This wealth of information is buried under Galactic and…

Instrumentation and Methods for Astrophysics · Physics 2015-01-20 Emma Chapman , Anna Bonaldi , Geraint Harker , Vibor Jelić , Filipe B. Abdalla , Gianni Bernardi , Jérôme Bobin , Fred Dulwich , Benjamin Mort , Mario Santos , Jean-Luc Starck

We present a novel technique for Cosmic Microwave Background (CMB) foreground subtraction based on the framework of blind source separation. Inspired by previous work incorporating local variation to Generalized Morphological Component…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-28 Sebastian Wagner-Carena , Max Hopkins , Ana Diaz Rivero , Cora Dvorkin

We prepare real-life Cosmic Microwave Background (CMB) lensing extraction with the forthcoming Planck satellite data, by studying two systematic effects related to the foregrounds contamination: the impact of foreground residuals after a…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-12 L. Perotto , J. Bobin , S. Plaszczynski , J. -L. Starck , A. Lavabre

Detecting neutral Hydrogen (H\,{\sc i}) via the 21~cm line emission from the intergalactic medium at $z\gtrsim 6$ has been identified as one of the most promising probes of the epoch of cosmic reionization -- a major phase transition of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 Nithyanandan Thyagarajan , Chris Carilli , Bojan Nikolic

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-13 Feng Shi , Haoxiang Chang , Le Zhang , Huanyuan Shan , Jiajun Zhang , Suiping Zhou , Ming Jiang , Zitong Wang

We present a simulation experiment of a pipeline based on machine learning algorithms for neutral hydrogen (HI) intensity mapping (IM) surveys with different telescopes. The simulation is conducted on HI signals, foreground emission,…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Lin-Cheng Li , Yuan-Gen Wang

Laser-induced breakdown spectroscopy is a preferred technique for fast and direct multi-elemental mapping of samples under ambient pressure, without any limitation on the targeted element. However, LIBS mapping data have two peculiarities:…

Applied Physics · Physics 2022-10-11 Riccardo Finotello , Mohamed Tamaazousti , Jean-Baptiste Sirven

The Internal Linear Combination (ILC) method is commonly employed to extract the cosmic microwave background (CMB) signal from multi-frequency observation maps. However, the performance of the ILC method tends to degrade when the…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-31 Zirui Zhang , Yang Liu , Si-Yu Li , Haifeng Li , Hong Li

\textsc{Hi} intensity mapping will provide maps of the large-scale distribution of neutral hydrogen (\textsc{Hi}) in the universe. These are prime candidates to be used to constrain primordial non-Gaussianity using the Large Scale Structure…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-03 José Fonseca , Michele Liguori

We present a comprehensive analysis of the 21 cm intensity mapping (IM) data from the Tianlai Cylinder Pathfinder Array (TCPA), focusing on multi-scale foreground mitigation and three-dimensional power spectrum estimation. Utilizing 20 days…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-01 Yikai Deng , Shifan Zuo , Jixia Li , Yougang Wang , Xuelei Chen

Cosmic microwave background radiation (CMB) observations are unavoidably contaminated by emission from various extra-galactic foregrounds, which must be removed to obtain reliable measurements of the cosmological signal. In this paper, we…

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…

Intensity mapping experiments survey the spectrum of diffuse line radiation rather than detect individual objects at high signal-to-noise. Spectral maps of unresolved atomic and molecular line radiation contain three-dimensional information…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-19 Eric R. Switzer , Tzu-Ching Chang , Kiyoshi W. Masui , Ue-Li Pen , Tabitha C. Voytek