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Related papers: A novel estimator of the polarization amplitude fr…

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Polarisation amplitude estimation is affected by a positive noise bias, particularly important in regions with low signal-to-noise ratio (SNR). We present a new approach to correct for this bias in the case there is additional information…

Instrumentation and Methods for Astrophysics · Physics 2016-06-29 Matias Vidal , J. P. Leahy , C. Dickinson

With the forthcoming release of high precision polarization measurements, such as from the Planck satellite, it becomes critical to evaluate the performance of estimators for the polarization fraction and angle. These two physical…

Instrumentation and Methods for Astrophysics · Physics 2015-02-11 L. Montier , S. Plaszczynski , F. Levrier , M. Tristram , D. Alina , I. Ristorcelli , J. -P. Bernard , V. Guillet

High precision polarization measurements open new opportunities for the study of the magnetic field structure as traced by polarimetric measurements of the interstellar dust emission. Polarization parameters suffer from bias in the presence…

Astrophysics of Galaxies · Physics 2017-03-15 D. Alina , L. Montier , I. Ristorcelli , J. -P. Bernard , F. Levrier , E. Abdikamalov

With the forthcoming release of high precision polarization measurements, such as from the Planck satellite, the metrology of polarization needs to improve. In particular, it is crucial to take into account full knowledge of the noise…

Instrumentation and Methods for Astrophysics · Physics 2015-02-11 L. Montier , S. Plaszczynski , F. Levrier , M. Tristram , D. Alina , I. Ristorcelli , J. -P. Bernard

Computing polarised intensities from noisy data in Stokes U and Q suffers from a positive bias that should be suppressed. To develop a correction method that, when applied to maps, should provide a distribution of polarised intensity that…

Instrumentation and Methods for Astrophysics · Physics 2017-04-05 Peter Müller , Rainer Beck , Marita Krause

Inspired by recent use of polarimetry to study the Cosmic Microwave Background and extragalatic supernovae, a foray into the statistical properties of Stokes parameters expressed in spherical coordinates is began, allowing circular…

Instrumentation and Methods for Astrophysics · Physics 2014-11-19 Jason L. Quinn

We show that it is possible to measure polarization with a polarimeter that gets rid of the seeing while still measuring at a frequency well below that of the seeing. We study a standard polarimeter made of two retarders and a beamsplitter.…

Instrumentation and Methods for Astrophysics · Physics 2016-04-20 A. Asensio Ramos

A fully analytic statistical formalism does not yet exist to describe radio-wavelength measurements of linearly polarized intensity that are produced using rotation measure synthesis. In this work we extend the analytic formalism for…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Christopher A. Hales , Bryan M. Gaensler , Ray P. Norris , Enno Middelberg

A number of polarization estimators have been developed for a variety of astrophysical applications to compensate measurements of linear polarization for a bias contributed by the instrumental noise. Most derivations of the estimators…

High Energy Astrophysical Phenomena · Physics 2025-03-11 M. M. McKinnon

We benchmark the reliability of the Rotation Measure (RM) synthesis algorithm using the 1005 Centaurus A field sources of Feain et al. (2009). The RM synthesis solutions are compared with estimates of the polarization parameters using…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 J. -P. Macquart , R. D. Ekers , I. Feain , M. Johnston-Hollitt

We develop two algorithms, based on maximum likelihood (ML) inference, for estimating the parameters of polarized radio sources which emit at a single rotation measure (RM), e.g., pulsars. These algorithms incorporate the flux density…

Instrumentation and Methods for Astrophysics · Physics 2017-10-25 D. H. F. M. Schnitzeler , K. J. Lee

We study the distribution functions of the CMB polarization angle $\psi$, focusing on the Planck 2018 CMB maps. We extend the model of Preece & Battye (2014) of Gaussian correlated $Q$ and $U$ Stokes parameters to allow nonzero means. When…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-12 James Creswell , Nadia Dachlythra , Hao Liu , Pavel Naselsky , Per Rex Christensen

This lab note introduces the "Stokes Camera," a simple and novel experimental arrangement for real-time measurement of spatial amplitude and polarisation and thus spatially resolved Stokes parameters. It uses a polarisation sensitive camera…

Optics · Physics 2023-08-31 Mitchell A. Cox , Carmelo Rosales Guzmán

Linearly polarized emission is described, in general, in terms of the Stokes parameters $Q$ and $U$, from which the polarization intensity and polarization angle can be determined. Although the polarization intensity and polarization angle…

Astrophysics of Galaxies · Physics 2018-01-31 C. A. Herron , B. M. Gaensler , G. F. Lewis , N. M. McClure-Griffiths

It is well known that if the power spectral density of a continuous time stationary stochastic process does not have a compact support, data sampled from that process at any uniform sampling rate leads to biased and inconsistent spectrum…

Statistics Theory · Mathematics 2010-06-09 Radhendushka Srivastava , Debasis Sengupta

The study of the linear and circular polarization in AGN allows one to gain detailed information about the properties of the magnetic fields in these objects. However, especially the observation of circular polarization (CP) with…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 E. Cenacchi , A. Kraus , A. Orfei , K. -H. Mack

A statistical framework is presented for the study of the orthogonally polarized modes of radio pulsar emission via the covariances between the Stokes parameters. To accommodate the typically heavy-tailed distributions of single-pulse radio…

Instrumentation and Methods for Astrophysics · Physics 2017-02-07 Willem van Straten , Caterina Tiburzi

We developed an instrument design capable of measuring linear X-ray polarization over a broad-band using conventional spectroscopic optics. A set of multilayer-coated flats reflects the dispersed X-rays to the instrument detectors. The…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Herman L. Marshall , Ralf Heilmann , Norbert Schulz , Kendrah Murphy

Detection thresholds in polarized intensity and polarization bias correction are investigated for surveys where the polarization information is obtained from RM synthesis. Considering unresolved sources with a single rotation measure, a…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Samuel J. George , Jeroen M. Stil , Ben W. Keller

A detailed and formal account of polarization measurements using Bayesian analysis is given based on the assumption of gaussian error for the Stokes parameters. This analysis is crucial for the measurement of the polarization degree and…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Jason L. Quinn
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