English
Related papers

Related papers: A Unified Calibration Framework for 21 cm Cosmolog…

200 papers

The 21cm line probes the evolution of matter perturbations over a wide range of redshifts, from the dark ages down to the completion of reionization. Observing the 21cm cosmological signal will extend our understanding of the evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-26 Xue-Wen Liu , Caroline Heneka , Luca Amendola

Radio-astronomical observations are increasingly contaminated by interference, and suppression techniques become essential. A powerful candidate for interference mitigation is adaptive spatial filtering. We study the effect of spatial…

Astrophysics · Physics 2014-10-13 Amir Leshem , Alle-Jan van der Veen

For the use of Gamma-Ray Bursts (GRBs) to probe cosmology in a cosmology-independent way, a new method has been proposed to obtain luminosity distances of GRBs by interpolating directly from the Hubble diagram of SNe Ia, and then…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 He Gao , Nan Liang , Zong-Hong Zhu

Precise cosmological measurements are essential for understanding the evolution of the universe and the nature of dark energy. The Five-hundred-meter Aperture Spherical Telescope (FAST), the most sensitive single-dish radio telescope, has…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-23 Jun-Da Pan , Peng-Ju Wu , Guo-Hong Du , Yichao Li , Xin Zhang

Telescopes aiming to measure 21cm emission from the Epoch of Reionization must toe a careful line, balancing the need for raw sensitivity against the stringent calibration requirements for removing bright foregrounds. It is unclear what the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Aaron Parsons , Jonathan Pober , Matthew McQuinn , Daniel Jacobs , James Aguirre

This paper presents a systematic literature review focusing on the application of machine learning techniques for deriving observational constraints in cosmology. The goal is to evaluate and synthesize existing research to identify…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Luis Rojas , Sebastián Espinoza , Esteban González , Carlos Maldonado , Fei Luo

Sky subtraction is the key technique in data reduction of multi-fiber spectra. Knowledge of the related instrument character is necessary to determine the method adopted in sky subtraction. In this study, we described the sky subtraction…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 Zhong-Rui Bai , Hao-Tong Zhang , Hai-Long Yuan , Guang-Wei Li , Jian-Jun Chen , Ya-Juan Lei , Hui-Qin Yang , Yi-Qiao Dong , Gang Wang , Yong-Heng Zhao

This paper presents a groundbreaking approach - the first online automatic geometric calibration method for radar and camera systems. Given the significant data sparsity and measurement uncertainty in radar height data, achieving automatic…

Computer Vision and Pattern Recognition · Computer Science 2025-05-29 Van-Tin Luu , Yon-Lin Cai , Vu-Hoang Tran , Wei-Chen Chiu , Yi-Ting Chen , Ching-Chun Huang

When combining data sets to perform parameter inference, the results will be unreliable if there are unknown systematics in data or models. Here we introduce a flexible methodology, BACCUS: BAyesian Conservative Constraints and Unknown…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 José Luis Bernal , John A. Peacock

In radio astronomy, accurate calibration is of crucial importance for the new generation of radio interferometers. More specifically, because of the potential presence of outliers which affect the measured data, robustness needs to be…

Instrumentation and Methods for Astrophysics · Physics 2018-08-01 Virginie Ollier , Mohammed Nabil El Korso , André Ferrari , Rémy Boyer , Pascal Larzabal

Classifier-guided diffusion models have emerged as a powerful approach for conditional image generation, but they suffer from overconfident predictions during early denoising steps, causing the guidance gradient to vanish. This paper…

Computer Vision and Pattern Recognition · Computer Science 2025-12-23 Seyed Alireza Javid , Amirhossein Bagheri , Nuria González-Prelcic

LiDAR-camera calibration is a precondition for many heterogeneous systems that fuse data from LiDAR and camera. However, the constraint from common field of view and the requirement for strict time synchronization make the calibration a…

Robotics · Computer Science 2019-07-31 Bo Fu , Yue Wang , Xiaqing Ding , Yanmei Jiao , Li Tang , Rong Xiong

We perform a detailed analysis of the latest CMB measurements (including BOOMERaNG, DASI, Maxima and CBI), both alone and jointly with other cosmological data sets involving, e.g., galaxy clustering and the Lyman Alpha Forest. We first…

Astrophysics · Physics 2009-09-25 Xiaomin Wang , Max Tegmark , Matias Zaldarriaga

We introduce a self-calibration method that can be applied to the intrinsic ellipticity--intrinsic ellipticity (II) and gravitational shear -- intrinsic ellipticity (GI) types of intrinsic alignment of galaxies. The method combines previous…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 Ji Yao , Mustapha Ishak , M. A. Troxel

Calibration of instrumental polarization is critical for measuring polarized radio emissions from astrophysical sources to extract the magnetic field information in astrophysical, heliospheric, and terrestrial plasmas. At meter wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2025-05-08 Devojyoti Kansabanik , Angelos Vourlidas , Soham Dey , Surajit Mondal , Divya Oberoi

We study the fundamental question of how to define and measure the distance from calibration for probabilistic predictors. While the notion of perfect calibration is well-understood, there is no consensus on how to quantify the distance…

Machine Learning · Computer Science 2023-04-03 Jarosław Błasiok , Parikshit Gopalan , Lunjia Hu , Preetum Nakkiran

We consider a cosmology in which a spherically symmetric large scale inhomogeneous enhancement or a void are described by an inhomogeneous metric and Einstein's gravitational equations. For a flat matter dominated universe the inhomogeneous…

Astrophysics · Physics 2008-11-26 J. W. Moffat

We present a new method that simultaneously solves for cosmology and galaxy bias on non-linear scales. The method uses the halo model to analytically describe the (non-linear) matter distribution, and the conditional luminosity function…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Frank van den Bosch , Surhud More , Marcello Cacciato , Houjun Mo , Xiaohu Yang

Constraints on cosmological parameters from upcoming measurements with the Mileura Widefield Array-Low Frequency Demonstrator (MWA-LFD) of the redshifted 21 cm power spectrum are forecast assuming a flat LCDM cosmology and that the…

Astrophysics · Physics 2008-11-26 Judd D. Bowman , Miguel F. Morales , Jacqueline N. Hewitt

One of the main challenges facing upcoming CMB experiments will be to distinguish the cosmological signal from foreground contamination. We present a comprehensive treatment of this problem and study how foregrounds degrade the accuracy…

Astrophysics · Physics 2009-10-07 Max Tegmark , Daniel J. Eisenstein , Wayne Hu , Angelica de Oliveira-Costa