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Many spectacular polarimetric images have been obtained in recent years with adaptive optics (AO) instruments at large telescopes because they profit significantly from the high spatial resolution. This paper summarizes some basic…

Instrumentation and Methods for Astrophysics · Physics 2022-08-01 H. M. Schmid

The goals of this work are to provide NIR polarimetry of the stellar sources in the central pc at the resolution of an 8m telescope for the first time, along with new insights into the nature of the known bright bow-shock sources. We use AO…

Astrophysics of Galaxies · Physics 2015-05-28 Rainer M. Buchholz , Gunther Witzel , Rainer Schödel , Andreas Eckart , Markus Bremer , Koraljka Muzic

We present results of a coronographic imaging search for circumstellar dust disks with the Adaptive Optics Near Infrared System (ADONIS) at the ESO 3.6m telescope in La Silla (Chile). 22 candidate stars, known to be orbited by a planet or…

Astrophysics · Physics 2009-11-10 O. Schuetz , H. Boehnhardt , E. Pantin , M. Sterzik , S. Els , J. Hahn , Th. Henning

The value of accurately knowing the absolute calibration of the polarizing elements in the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) becomes especially important when conducting studies which require measuring degrees of…

Astrophysics · Physics 2009-11-11 D. Batcheldor , A. Robinson , D. Axon , D. C. Hines , W. Sparks , C. Tadhunter

Many different methods exist for reducing data obtained when an astronomical source is studied with a two-channel polarimeter, such as a Wollaston prism system. This paper presents a rigorous method of reducing the data from raw aperture…

Astrophysics · Physics 2007-05-23 G. Leyshon

Imaging polarimetry is a powerful tool for detecting and characterizing exoplanets and circumstellar environments. Polarimetry allows a separation of the light coming from an unpolarized source such as a star and the polarized source such…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 H. Canovas , M. Rodenhuis , S. V. Jeffers , M. Min , C. U. Keller

In the last decade, imaging polarimeters based on micropolarizer arrays have been developed for use in terrestrial remote sensing and metrology applications. Micropolarizer-based sensors are dramatically smaller and more mechanically robust…

Instrumentation and Methods for Astrophysics · Physics 2018-04-26 Dmitry Vorobiev , Zoran Ninkov , Neal Brock

The angle of rotation of any target about the radar line of sight (LOS) is known as the polarization orientation angle. The orientation angle is found to be non-zero for undulating terrains and man-made targets oriented away from the radar…

Classical Physics · Physics 2017-04-26 Avik Bhattacharya

High resolution near-infrared adaptive optics imaging and polarimetry have been obtained of the Homunculus Nebula and its central star Eta Carinae (HD 93308). Maps of the linear polarization at a resolution of <0.2'' have been made in the…

Astrophysics · Physics 2007-05-23 J. R. Walsh , N. Ageorges

We consider a method for obtaining information on polarization of astronomical objects radiation at diffraction limited resolution - differential speckle polarimetry. As an observable we propose to use averaged cross spectrum of two…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Boris Safonov

The findings of a nine orbit calibration plan carried out during HST Cycle 15, to fully determine the NICMOS camera 2 (2.0 micron) polarization calibration to high accuracy, are reported. Recently Ueta et al. and Batcheldor et al. have…

We describe a method for determining the limb polarization and limb darkening of stars in eclipsing binary systems, by inverting photometric and polarimetric light curves. Because of the ill-conditioning of the problem, we use the…

Astrophysics · Physics 2009-10-30 I J Coleman , N Gray , J F L Simmons

The ability of NICMOS to perform high accuracy polarimetry is currently hampered by an uncalibrated residual instrumental polarization at a level of 1.2-1.5%. To better quantify and characterize this residual we obtained observations of…

Polarization imaging can yield crucial information in multiple applications of remote sensing, such as characterization of clouds, aerosols, and the Aurora Borealis. Some applications require sub-percent polarimetric sensitivity and…

Instrumentation and Methods for Astrophysics · Physics 2024-05-14 Thijs Stockmans , Naor Scheinowitz , Erwoud van der Linden , Irina Malysheva , Kira Strelow , Martijn Smit , Frans Snik

This paper presents a method of passive non-line-of-sight (NLOS) imaging using polarization cues. A key observation is that the oblique light has a different polarimetric signal. It turns out this effect is due to the polarization axis…

Image and Video Processing · Electrical Eng. & Systems 2019-12-02 Kenichiro Tanaka , Yasuhiro Mukaigawa , Achuta Kadambi

Optical polarimeters are typically calibrated using measurements of stars with known and stable polarization parameters. However, there is a lack of such stars available across the sky. Many of the currently available standards are not…

We have built and tested a compact, low-cost, but very-high-performance astronomical polarimeter based on a continuously rotating half-wave plate and a high-speed imaging detector. The polarimeter is suitable for small telescopes up to ~1 m…

Instrumentation and Methods for Astrophysics · Physics 2023-02-08 Jeremy Bailey , Daniel V. Cotton , Ain De Horta , Lucyna Kedziora-Chudczer , Om Shastri

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 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…

Astrophysics · Physics 2009-11-11 D. M. Harrington , J. R. Kuhn , K. Whitman

Active polarimetric imagery is a powerful tool for accessing the information present in a scene. Indeed, the polarimetric images obtained can reveal polarizing properties of the objects that are not avalaible using conventional imaging…

Information Retrieval · Computer Science 2016-08-16 Muriel Roche , Philippe Réfrégier
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