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X-ray polarimetric measurements are based on studying the distribution of the directions of scattered photons or photoelectrons and on the search of a sinusoidal modulation with a period of {\pi}. We developed two tools for investigating…

Instrumentation and Methods for Astrophysics · Physics 2018-01-08 Enrico Massaro , Sergio Fabiani , Riccardo Campana , Enrico Costa , Ettore Del Monte , Fabio Muleri , Paolo Soffitta

The response of a pair of differently polarized antennas is determined by their polarization states AND a phase between them which has a geometric part which becomes discontinuous at singular points in the parameter space. Such phase…

Astrophysics · Physics 2016-08-30 Rajendra Bhandari

With ever increasing availability of terahertz fields, it is important to find suitable detection techniques without compromising the measured dynamic range. Electro-optic terahertz sampling techniques, which are commonly used to detect…

Optics · Physics 2020-08-26 Gregory Bell , Michael Hilke

In this paper we investigate the polarization property of the radiation amplified by astronomical masers in the presence of a strong magnetic field. Our model explicitly takes into account the broadband nature of the radiation field and the…

Astrophysics of Galaxies · Physics 2015-05-13 Dinh-V-Trung

Polarized atomic ensembles play a crucial role in precision measurements. We demonstrate a novel method of creating atomic polarization in an alkali vapor in a continuous-wave regime. The method relies on a combination of optical pumping by…

Atomic Physics · Physics 2021-10-22 A. Tretiakov , C. A. Potts , Y. Y. Lu , J. P. Davis , L. J. LeBlanc

Direction-dependent instrumental polarisation introduces wide-field polarimetric aberrations and limits the dynamic range of low-frequency interferometric images. We therefore provide a detailed two-dimensional analysis of the Giant…

Instrumentation and Methods for Astrophysics · Physics 2014-07-03 J. S. Farnes

We utilize the localization analysis method to precisely determine the light beam positions with the spatial separation beyond the optical diffraction limit. By such a direct spatial measurement, the associated optical setup is built to…

Instrumentation and Detectors · Physics 2018-10-11 Hoi Chun Chiu , Zhuohui Zeng , Luwei Zhao , Teng Zhao , Shengwang Du , Xian Chen

The polarization of light conveys crucial information about the spatial ordering and optical properties of a specimen. However, precise polarization measurement in challenging conditions, including constrained spaces, low light levels, and…

Optics · Physics 2026-03-10 Martin Bielak , Dominik Vašinka , Miroslav Ježek

A statistical model of the polarization of pulsar radio emission is used to derive the general statistics of a polarization vector's orientation angles. The theoretical distributions are compared with orientation angle histograms computed…

Astrophysics · Physics 2009-11-11 Mark M. McKinnon

We explore the alternatives for interrogating a fiber sensor from the polarization point of view, and demonstrate a better accuracy with dual polarization probing for coherent phi-OTDR compared with single polarization probing.

Signal Processing · Electrical Eng. & Systems 2021-11-12 Sterenn Guerrier , Christian Dorize , Elie Awwad , Jérémie Renaudier

We present a new method for high precision measurements of polarization rotation in the frequency range from 0.2 to 2.2 THz using a fiber coupled time-domain THz spectrometer. A free standing wire-grid polarizer splits THz light into…

Optics · Physics 2023-12-21 Zhenisbek Tagay , Ralph Romero , N. P. Armitage

An approach for measuring linear X-ray polarization over a broad-band using conventional spectroscopic optics is described. A set of multilayer-coated flats reflect the dispersed X-rays to the instrument detectors. The intensity variation…

Astrophysics · Physics 2009-11-13 Herman L. Marshall

Our goal is to test the feasibility to obtain accurate measurements of the continuum polarization from high-resolution spectra using the spectropolarimetric mode of ESPaDOnS. We used the new pipeline OPERA to reduce recent and archived…

Instrumentation and Methods for Astrophysics · Physics 2015-01-14 A. Pereyra , C. V. Rodrigues , E. Martioli

Polarized neutrons are a powerful probe to investigate magnetism in condensed matter on length scales from single atomic distances to micrometers. With the ongoing advancement of neutron optics, that allow to transport beams with increased…

Instrumentation and Detectors · Physics 2017-08-02 Jochen Stahn , Artur Glavic

A calibration scheme is presented for improved polarization state measurement of terahertz pulses. In this scheme the polarization response of a two-contact terahertz photoconductive detector is accurately measured, and is used to correct…

Optics · Physics 2012-01-25 M. Neshat , N. P. Armitage

Measuring the alignment of polarized radio sources requires comparing vectors at different locations on the sky, i.e. on a sphere. A test of alignment is derived herein. While both large scale and coordinate independent, the test avoids the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-13 Richard Shurtleff

Heterodyne receivers register the sky signal on either a circular polarization basis (where it is split into left-hand and right-hand circular polarization) or a linear polarization basis (where it is split into horizontal and vertical…

Instrumentation and Methods for Astrophysics · Physics 2016-03-09 Ivan Marti-Vidal , Alan Roy , John Conway , Anton J. Zensus

We present the results of a systematic observational campaign designed to search for microvariability in the optical polarization of BL Lac objects. We have observed a sample formed by 8 X-ray-selected and 10 radio-selected sources, looking…

Astrophysics · Physics 2009-11-11 I. Andruchow , G. E. Romero , S. A. Cellone

We present the electromagnetic model of a dual circular polarization antenna-feed system, consisting of a corrugated feedhorn, a polarizer and an orthomode transducer. This model was developed for the passive front-end implemented in the…

Instrumentation and Methods for Astrophysics · Physics 2019-05-22 S. Realini , C. Franceschet , A. Mennella

Polarisation holography generally demands polarisation-sensitive holograms for reconstructing either polarisation-multiplexed holographic images or polarisation-sensitive image channels. To date, polarisation holography is underpinned by…

Optics · Physics 2022-07-22 Haoran Ren