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To achieve the sensitivity required to detect signals from neutral hydrogen from the Cosmic Dawn and Epoch of Reionisation it is critical to have a well-calibrated instrument which has a stable calibration over the course of the…

Instrumentation and Methods for Astrophysics · Physics 2026-03-04 Christian J. Kirkham , Dominic J. Anstey , Eloy de Lera Acedo

The first generation of redshifted 21 cm detection experiments, carried out with arrays like LOFAR, MWA and GMRT, will have a very low signal-to-noise ratio per resolution element (\sim 0.2). In addition, whereas the variance of the…

Photon-counting computed tomography (PCCT) has emerged as a promising imaging technique, enabling spectral imaging and material decomposition (MD). However, images typically suffer from a low signal-to-noise ratio (SNR) due to constraints…

We perform a Fisher analysis to estimate the expected constraints on the Epoch of Reionization (EoR) model parameters (i.e., minimum virial temperature, the ionizing efficiency and the mean free path of ionizing photons) taking into account…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-04 Hayato Shimabukuro , Shintaro Yoshiura , Keitaro Takahashi , Shuichiro Yokoyama , Kiyotomo Ichiki

Sensors measuring real-life physical processes are ubiquitous in today's interconnected world. These sensors inherently bear noise that often adversely affects performance and reliability of the systems they support. Classic filtering-based…

Detecting a signal from the Epoch of Reionisation (EoR) requires an exquisite understanding of galactic and extra-galactic foregrounds, low frequency radio instruments, instrumental calibration, and data analysis pipelines. In this work we…

Instrumentation and Methods for Astrophysics · Physics 2020-02-27 Ronniy C. Joseph , C. M. Trott , R. B. Wayth , A. Nasirudin

This report studies diffusion posterior sampling (DPS) for single-image super-resolution (SISR) under a known degradation model. We implement a likelihood-guided sampling procedure that combines an unconditional diffusion prior with…

Computer Vision and Pattern Recognition · Computer Science 2025-12-29 Abu Hanif Muhammad Syarubany

This letter introduces a dual application of denoising diffusion probabilistic model (DDPM)-based channel estimation algorithm integrating data denoising and augmentation. Denoising addresses the severe noise in raw signals at pilot…

Signal Processing · Electrical Eng. & Systems 2025-10-06 Yupeng Li , Ruhao Zhang , Yitong Liu , Chunju Shao , Jing Jin , Shijian Gao

Global 21cm experiments aim to measure the sky averaged HI absorption signal from cosmic dawn and the epoch of reionisation. However, antenna chromaticity coupling to bright foregrounds can introduce distortions into the observational data…

Instrumentation and Methods for Astrophysics · Physics 2021-11-12 Dominic Anstey , John Cumner , Eloy de Lera Acedo , Will Handley

The Epoch of Reionization (EoR) 21-cm signal is expected to become increasingly non-Gaussian as reionization proceeds. We have used semi-numerical simulations to study how this affects the error predictions for the EoR 21-cm power spectrum.…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-03 Rajesh Mondal , Somnath Bharadwaj , Suman Majumdar , Apurba Bera , Ayan Acharyya

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…

We study the inductive biases of diffusion models with a conditioning-variable, which have seen widespread application as both text-conditioned generative image models and observation-conditioned continuous control policies. We observe that…

Machine Learning · Computer Science 2025-12-23 Daniel Pfrommer , Zehao Dou , Christopher Scarvelis , Max Simchowitz , Ali Jadbabaie

Correcting for detector effects in experimental data, particularly through unfolding, is critical for enabling precision measurements in high-energy physics. However, traditional unfolding methods face challenges in scalability,…

Data Analysis, Statistics and Probability · Physics 2024-11-28 Camila Pazos , Shuchin Aeron , Pierre-Hugues Beauchemin , Vincent Croft , Zhengyan Huan , Martin Klassen , Taritree Wongjirad

We propose a general framework for conditional sampling in PDE-based inverse problems, targeting the recovery of whole solutions from extremely sparse or noisy measurements. This is accomplished by a function-space diffusion model and…

Machine Learning · Computer Science 2026-02-06 Jiachen Yao , Abbas Mammadov , Julius Berner , Gavin Kerrigan , Jong Chul Ye , Kamyar Azizzadenesheli , Anima Anandkumar

We propose a new approach to improve the precision of astrophysical parameter constraints for the 21cm signal from the epoch of reionisation (EoR). Our method introduces new sets of summary statistics, hereafter `evolution compressed'…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-12 Ian Hothi , Erwan Allys , Benoit Semelin , Francois Boulanger

A proposed method for dealing with foreground emission in upcoming 21-cm observations from the epoch of reionization is to limit observations to an uncontaminated window in Fourier space. Foreground emission can be avoided in this way,…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-23 Hannes Jensen , Suman Majumdar , Garrelt Mellema , Adam Lidz , Ilian T. Iliev , Keri L. Dixon

The epoch of reionization is one of the least known chapters in the evolutionary history of the Universe. This thesis investigates two major approaches to unveil the reionization history of the Universe using HI 21-cm maps.The most…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-04 Kanan K. Datta

Diffusion posterior sampling conditions diffusion priors on measurements, but data-consistency updates are typically scaled by hand-tuned guidance weights and can destabilize sampling under stiff, operator-dependent curvature. We replace…

Machine Learning · Computer Science 2026-05-28 Seunghyeok Shin , Minwoo Kim , Dabin Kim , Hongki Lim

BayesEoR is a GPU-accelerated, MPI-compatible Python package for estimating the power spectrum of redshifted 21-cm emission from interferometric observations of the Epoch of Reionization (EoR). Utilizing a Bayesian framework, BayesEoR…

Instrumentation and Methods for Astrophysics · Physics 2025-01-23 Peter H. Sims , Jacob Burba , Jonathan C. Pober

Detection of the \hi~ 21-cm power spectrum is one of the key science drivers of several ongoing and upcoming low-frequency radio interferometers. However, the major challenge in such observations come from bright foregrounds, whose accurate…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-29 Madhurima Choudhury , Abhirup Datta , Suman Majumdar
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