International Cooperation for Innovations in Sensitive Polarimetry

Project Profile

Polarimetry is a powerful technique for revealing two- and three-dimensional structures in astrophysical objects beyond the spatial resolution provided by direct imaging at any telescope.

The goals of this cooperation are

  • to explore novel physical mechanisms for polarized light,
  • to develop an innovative polarimetric system with advanced mmodulation schemes and employ it on new-technology 1-2m class telescopes dedicated for polarimetric surveys,
  • to establish a lasting cooperation between two superior astronomical observatories on Canarias and Hawaii

The distinctive international partnership established in this project will enable scientific and technological developments well beyond the current state-of-the-art.

Key questions

This project brings together some of the world experts in theoretical and experimental polarimetry within an inter-disciplinary context of solar and night-time astrophysics. We concentrate our effort on adressing the following fundamental questions:

  • How magnetic fields are generated in objects having very deep convection zones or being fully convective?
  • How the circumstellar environment evolves during the dynamic process of star and planet formation?
  • What are the properties and inner structure of exoplanets?

Progress Report

Fig. 1: The blue channel of the InnoPol on the optical table. Basic components are the CCD detector, FLC modulator and motor-controlled polarization with a collimated broad-band input beam

Constructing an innovative polarimetric system InnoPol is one of our major goals. In 2011, we have developed optical and electronic schemes of the system and purchased ist critical elements, such as bidirectional charge shifting CCDs, retarders (FLC and Swift LC modulators), polarizers, and a number of mechanical, electronic and optical elements. Figure 1 shows the system mounted on the optical table in the lab where all parts are being tested individually and in ensemble. In particular, the FLCs are modulated at 100Hz synchronous with charge shuffling on the CCDs, as required for higher polarimetric accuracy. The lab data used to calibrate systematic errors at different modulation frequencies and wavelengths. In 2012, the system will be tested at the telescope. The InnoPol design and test results were presented at the international workshop "Polarimetry with Extremly Large Telescopes", Utrecht, 2011.