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Linear (spectro) polarimetry is usually performed using separate photon flux measurements after spatial or temporal polarization modulation. Such classical polarimeters are limited in sensitivity and accuracy by systematic effects and…

Optics · Physics 2010-05-28 Frans Snik , Theodora Karalidi , Christoph U. Keller

We present a new approach for correcting instrumental polarization by modeling the non-depolarizing effects of a complex series of optical elements to determine physically realizable Mueller matrices. Provided that the Mueller matrix of the…

Instrumentation and Methods for Astrophysics · Physics 2022-05-18 Sarah A. Jaeggli , Thomas A. Schad , Lucas A. Tarr , David M. Harrington

We reduced ESO's archival linear spectropolarimetry data (4000-9000\AA) of 6 highly polarized and 8 unpolarized standard stars observed between 2010 and 2016, for a total of 70 epochs, with the FOcal Reducer and low dispersion Spectrograph…

Instrumentation and Methods for Astrophysics · Physics 2016-10-12 Aleksandar Cikota , Ferdinando Patat , Stefan Cikota , Tamar Faran

We derive a generalization of forward fitting for X-ray spectroscopy to include linear polarization of X-ray sources, appropriate for the anticipated next generation of space-based photoelectric polarimeters. We show that the inclusion of…

Instrumentation and Methods for Astrophysics · Physics 2017-04-05 Tod E. Strohmayer

Context: Polarimetry is a very powerful tool to uncover various properties of astronomical objects that remain otherwise hidden in standard imaging or spectroscopic observations. However, the reliable measurement of the low polarization…

Instrumentation and Methods for Astrophysics · Physics 2020-02-12 S. González-Gaitán , A. M. Mourão , F. Patat , J. P. Anderson , A. Cikota , K. Wiersema , A. B. Higgins , K. Silva

We present an approach to spectropolarimetry which requires neither moving parts nor time dependent modulation, and which offers the prospect of achieving high sensitivity. The technique applies equally well, in principle, in the optical,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 William Sparks , Thomas A. Germer , John MacKenty , Frans Snik

In this paper we present an error analysis for polarimetric data obtained with dual-beam instruments. After recalling the basic concepts, we introduce the analytical expressions for the uncertainties of polarization degree and angle. These…

Astrophysics · Physics 2009-11-11 Ferdinando Patat , Martino Romaniello

We present a new `supercalibration' technique for measuring systematic distortions in the wavelength scales of high resolution spectrographs. By comparing spectra of `solar twin' stars or asteroids with a reference laboratory solar…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 J. B. Whitmore , M. T. Murphy

We describe, and test, a method of obtaining spectrally and spatially sampled Stokes polarimetry measurements based on star test polarimetry enabled by a stress engineered optic (SEO). When the SEO is placed in the pupil plane of an imaging…

Instrumentation and Detectors · Physics 2026-03-17 David E. Spiecker , Thomas G. Brown

An eight stage balanced modulation scheme for dual beam polarimetry is presented in this paper. The four Stokes parameters are weighted equally in all the eight stages of modulation resulting in total polarimetric efficiency of unity. The…

Astrophysics · Physics 2007-10-10 K. Nagaraju , K. B. Ramesh , K. Sankarasubramanian , K. E. Rangarajan

Our knowledge of the lower solar atmosphere is mainly obtained from spectropolarimetric observations, which are often carried out in the red or infrared spectral range and almost always cover only a single or a few spectral lines. Here we…

Instrumentation and Methods for Astrophysics · Physics 2019-01-30 T. L. Riethmüller , S. K. Solanki

Stereoscopic spectral imaging is an observing technique that affords rapid acquisition of limited spectral information over an entire image plane simultaneously. Light from a telescope is dispersed into multiple spectral orders, which are…

Astrophysics · Physics 2007-05-23 Craig E. DeForest , Charles C. Kankelborg

Laser speckle is generated by the multiple interference of light through a disordered medium. Here we study the premise that the speckle pattern retains information about the polarisation state of the incident field. We analytically verify…

Optics · Physics 2020-05-13 Morgan Facchin , Graham D. Bruce , Kishan Dholakia

The performance of electron energy-loss spectrometers can often be limited by their electron-optical aberrations. Due to recent developments in high energy-resolution and momentum-resolved electron energy loss spectroscopy (EELS), there is…

Materials Science · Physics 2023-02-28 Yueming Guo , Andrew R. Lupini

We present a technique to determine the polarization properties of a telescope through observations of spectral lines that have no intrinsic linear polarization signals. For such spectral lines, any observed linear polarization must be…

Instrumentation and Methods for Astrophysics · Physics 2018-04-05 A. Derks , C. Beck , V. Martinez Pillet

The analysis of high spectral resolution spectroscopic and spectropolarimetric observations constitute a very powerful way of inferring the dynamical, thermodynamical, and magnetic properties of distant objects. However, these techniques…

Solar and Stellar Astrophysics · Physics 2015-06-11 A. Asensio Ramos , R. Manso Sainz

Stellar spectropolarimetry is a relatively new remote sensing tool for exploring stellar atmospheres and circumstellar environments. We present the results of our HiVIS survey and a multi-wavelength ESPaDOnS follow-up campaign showing…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 D. M. Harrington , J. R. Kuhn

This paper is devoted to the primary spectro-polarimetric observation performed at the New Vacuum Solar Telescope of China since 2017, and our aim is to precisely evaluate the real polarimetric accuracy and sensitivity of this polarimetry…

Solar and Stellar Astrophysics · Physics 2020-05-06 Jun-Feng Hou , Zhi Xu , Shu Yuan , Yu-Chao Chen , Jian-Guo Peng , Dong-Guang Wang , Jun Xu , Yuan-Yong Deng , Zhen-Yu Jin , Kai-Fan Ji , Zhong Liu

Well-calibrated spectropolarimetry studies at resolutions of $R>$10,000 with signal-to-noise ratios (SNRs) better than 0.01\% across individual line profiles, are becoming common with larger aperture telescopes. Spectropolarimetric studies…

Instrumentation and Methods for Astrophysics · Physics 2015-06-24 David Harrington , J. R. Kuhn , Rebecca Nevin

We outline the theory and practice of measuring the four Stokes parameters of spectral lines in emission/absorption observations. We apply these concepts to our Arecibo HI absorption line data and present the results. We include a detailed…

Astrophysics · Physics 2007-05-23 Carl Heiles T. H. Troland
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