Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.14/8635
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- Title
- PlanetPol : a very high sensitivity polarimeter
- Related
- Publications of the Astronomical Society of the Pacific, Vol. 118, Issue 847, p.1302-1318
- DOI
- 10.1086/507955
- Publisher
- University of Chicago Press
- Date
- 2006
- Author/Creator
- Hough, J. H
- Author/Creator
- Lucas, P. W
- Author/Creator
- Bailey, J. A
- Author/Creator
- Tamura, M
- Author/Creator
- Hirst, E
- Author/Creator
- Harrison, D
- Author/Creator
- Bartholomew-Biggs, M
- Description
- We have built and used on several occasions an optical broadband stellar polarimeter, PlanetPol, which employs photoelastic modulators and avalanche photodiodes and achieves a photon-noise-limited sensitivity of at least 1 in 10⁶ in fractional polarization. Observations of a number of polarized standards taken from the literature show that the accuracy of polarization measurements is ~1%. We have developed a method for accurately measuring the polarization of altitude-azimuth mounted telescopes by observing bright nearby stars at different parallactic angles, and we find that the on-axis polarization of the William Herschel Telescope is typically ~15 × 10⁻⁶, measured with an accuracy of a few parts in 10⁷. The nearby stars (distance less than 32 pc) are found to have very low polarizations, typically a few ×10⁻⁶, indicating that very little interstellar polarization is produced close to the Sun and that their intrinsic polarization is also low. Although the polarimeter can be used for a wide range of astronomy, the very high sensitivity was set by the goal of detecting the polarization signature of unresolved extrasolar planets.
- Description
- 17 page(s)
- Subject Keyword
- instrumentation, polarimeters
- Subject Keyword
- techniques, polarimetric
- Resource Type
- journal article
- Organisation
- Macquarie University. Australian Centre for Astrobiology
- Identifier
- http://hdl.handle.net/1959.14/8635
- Identifier
- ISSN:0004-6280
- Identifier
- mq-rm-2006000728
- Language
- eng
- Reviewed
