English
Related papers

Related papers: Coaxing Cosmic 21cm Fluctuations from the Polarize…

200 papers

21 cm cosmology is a promising new probe of the evolution of visible matter in our universe, especially during the poorly-constrained Cosmic Dawn and Epoch of Reionization. However, in order to separate the 21 cm signal from bright…

A new generation of interferometric instruments is emerging which aim to use intensity mapping of redshifted $21\,$cm radiation to measure the large-scale structure of the Universe at $z\simeq 1-2$ over wide areas of sky. While these…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Martin White , Nikhil Padmanabhan

Polarimetric observations of the twilight sky are effective for the investigations of scattering properties of the atmosphere at different altitudes. Modern computer technique allows to reduce the influence of multiple scattering on the…

Atmospheric and Oceanic Physics · Physics 2007-05-23 O. V. Postylyakov , O. S. Ugolnikov , I. A. Maslov , A. N. Masleev

We present a fast method for estimating the cosmic microwave background polarization power spectra using unbiased estimates of heuristically-weighted correlation functions. This extends the O(N_pix^(3/2)) method of Szapudi et al. (2001) to…

Astrophysics · Physics 2009-11-07 Gayoung Chon , Anthony Challinor , Simon Prunet , Eric Hivon , Istvan Szapudi

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

Power spectrum estimation and evaluation of associated errors in the presence of incomplete sky coverage; non-homogeneous, correlated instrumental noise; and foreground emission is a problem of central importance for the extraction of…

Astrophysics · Physics 2016-08-30 J. Jewell , S. Levin , C. H. Anderson

We investigate the performance of a simple Bayesian fitting approach to correct the cosmic microwave background (CMB) B-mode polarization for gravitational lensing effects in the recovered probability distribution of the tensor-to-scalar…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-28 M. Remazeilles , C. Dickinson , H. K. Eriksen , I. K. Wehus

Interferometric radio astronomy data require the effects of limited coverage in the Fourier plane to be accounted for via a deconvolution process. For the last 40 years this process, known as `cleaning', has been performed almost…

Instrumentation and Methods for Astrophysics · Physics 2016-06-15 Luke Pratley , Melanie Johnston-Hollitt

Understanding large-angular-scale galactic foregrounds is crucial for future CMB experiments aiming to detect $B$-mode polarization from primordial gravitational waves. Traditionally, the dust component has been separated using its…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-18 Guangyu Zhang , Chi-Ting Chiang , Chris Sheehy , Anže Slosar , Jian Wang

Recent CMB observations have resulted in very precise observational data. A robust and reliable CMB reconstruction technique can lead to efficient estimation of the cosmological parameters. We demonstrate the performance of our methodology…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-31 Albin Joseph , Ujjal Purkayastha , Rajib Saha

We present a formalism for analyzing a full-sky temperature and polarization map of the cosmic microwave background. Temperature maps are analyzed by expanding over the set of spherical harmonics to give multipole moments of the two-point…

Astrophysics · Physics 2009-10-28 Marc Kamionkowski , Arthur Kosowsky , Albert Stebbins

All coronagraphic instruments for exoplanet high-contrast imaging need wavefront correction systems to reject optical aberrations and create sufficiently dark holes. Since the most efficient wavefront correction algorithms (controllers and…

Instrumentation and Methods for Astrophysics · Physics 2018-10-09 He Sun , N. Jeremy Kasdin , Robert Vanderbei

We present constraints on primordial B modes from large angular scale cosmic microwave background polarisation anisotropies measured with the Planck satellite. To remove Galactic polarised foregrounds, we use a Bayesian parametric component…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-30 Roger de Belsunce , Steven Gratton , George Efstathiou

The detection of Cosmic Microwave Background primordial $B$-mode polarization would constitute a ``smoking gun" signal of primordial gravitational waves. However, this measurement requires accurate removal of polarized Galactic foregrounds…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Luca Gomez Bachar , Cora Dvorkin , Alberto Daniel Supanitsky

A number of important cosmological questions can be addressed only by probing perturbation modes on the largest accessible scales. One promising probe of these modes is the Kamionkowski-Loeb effect, i.e., the polarization induced in the…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-17 Arsalan Adil , Reid Koutras , Emory F. Bunn

A discrete tomography method has been developed that is able to reconstruct three-dimensional coronal mass ejection (CME) density structure. We test the method by producing synthetic coronagraph imagery for three events using the…

The Cosmology Large Angular Scale Surveyor (CLASS) will measure the polarization of the Cosmic Microwave Background to search for and characterize the polarized signature of inflation. CLASS will operate from the Atacama Desert and observe…

Polarization plays an important role in various time-domain astrophysics to understand the magnetic fields, geometry, and environments of spatially unresolved variable sources. In this paper we present the results of laboratory and on-sky…

Instrumentation and Methods for Astrophysics · Physics 2020-04-29 Manisha Shrestha , Iain A. Steele , Andrez S. Piascik , Helen Jermak , Robert J. Smith , Chris M. Copperwheat

We present the first detailed case study using quadratic estimators (QE) to diagnose and remove systematics present in observed Cosmic Microwave Background (CMB) maps. In this work we focus on the temperature to polarization leakage. We use…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-13 Joel Williams , Nialh McCallum , Aditya Rotti , Daniel Thomas , Richard Battye , Michael L. Brown

Weak gravitational lensing of the 21 cm radiation is expected to be an important cosmological probe for post-reionization physics. We investigate the reconstruction of the matter density perturbations using a quadratic minimum variance…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-10 Priyesh Chakraborty , Anthony R. Pullen
‹ Prev 1 4 5 6 7 8 10 Next ›