相关论文: Achromatizing a liquid-crystal spectropolarimeter:…
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…
We designed, built, and calibrated a new spectropolarimeter for the HiVIS spectrograph (R 12000-49000) on the AEOS telescope. We also did a polarization calibration of the telescope and instrument. We will introduce the design and use of…
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…
Using the HiVIS spectropolarimeter built for the Haleakala 3.7m AEOS telescope in Hawaii, we are collecting a large number of high precision spectropolarimetrc observations of stars. In order to precisely measure very small polarization…
Metasurfaces composed of anisotropic subwavelength structures provide an ultrathin platform for a compact, real-time polarimeter. However, applications in polychromatic scenes are restricted by the limited operating bandwidths and degraded…
High-resolution spectropolarimetry is a useful astronomical technique, in particular to study stellar magnetic fields. It has been extensively used in the past but mostly in the visible range. Space missions equipped with high-resolution…
Accurate calibration of polarization dependent optical elements is often necessary in optical experiments. A versatile polarimeter device to measure the polarization state of light is a valuable tool in these experiments. Here we report a…
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.…
To obtain full Stokes spectra in multi-wavelength windows simultaneously, we developed a new spectro-polarimeter on the Domeless Solar Telescope at Hida Observatory. The new polarimeter consists of a 60 cm aperture vacuum telescope on an…
A simple, self-calibrating, rotating-waveplate polarimeter is largely insensitive to light intensity fluctuations and is shown to be useful for determining the Stokes parameters of light. This study shows how to minimize the in situ…
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…
Here we describe the implementation and calibration of a streaked visible spectrometer (SVS) for optical pyrometry and emission/absorption spectroscopy on light gas gun platforms in the UC Davis Shock Compression Laboratory. The diagnostic…
In this diploma thesis, the calibration of the vector polarimeter POLIS will be described. The instrument is built by the Kiepenheuer-Institut fuer Sonnenphysik (Freiburg/Germany) in cooperation with the High Altitude Observatory…
In a dual-frequency liquid crystal (DFLC), when the frequency of the applied voltage is more than a critical value ($f_c$), the dielectric anisotropy of the material changes from positive to negative. This causes the director to switch its…
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…
The wavelength calibration of spectrographs is an essential but challenging task in many disciplines. Calibration is traditionally accomplished by imaging the spectrum of a light source containing features that are known to appear at…
The DKIST is designed to deliver accurate spectropolarimetric calibrations across a wide wavelength range and large field of view for solar observations. Instruments deliver spectral resolving powers up to 300,000 in multiple cameras of…
Four Stokes parameters (1852) define the polarisation state of light. Measured changes of the Stokes vector of light traversing an inhomogeneous sample are linked to the local anisotropies of absorption and refraction and are harnessed over…
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…
In order to accept very forward angle scattering particles, Jefferson Lab HKS experiment uses an on-target zero degree dipole magnet. The usual spectrometer optics calibration procedure has to be modified due to this on-target field. This…