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Published on: February 28, 2016
Measurement of polarization with the Degree Angular Scale Interferometer.
E M Leitch1, J M Kovac, C Pryke
1Department of Astronomy & Astrophysics, Center for Astrophysical Research in Antarctica, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA. eml@polestar.uchicago.edu
Nature
|December 20, 2002
Summary
The Degree Angular Scale Interferometer (DASI) successfully measured cosmic microwave background (CMB) polarization, a crucial property for understanding the early Universe. This breakthrough provides new insights into the Universe
Area of Science:
- Cosmology
- Astrophysics
- Observational Astronomy
Background:
- Cosmic Microwave Background (CMB) radiation offers precise insights into the early Universe (approx. 400,000 years old).
- Key CMB properties include frequency spectrum (temperature), temperature fluctuations, and polarization fluctuations across angular scales.
- Measuring CMB polarization has been a significant observational challenge.
Purpose of the Study:
- To describe the Degree Angular Scale Interferometer (DASI) and its capabilities.
- To report on polarization-sensitive observations of the CMB conducted by DASI.
- To advance the measurement of CMB polarization, a fundamental property of the early Universe.
Main Methods:
- Utilized the Degree Angular Scale Interferometer (DASI), an array of radio telescopes.
- Conducted polarization-sensitive observations of the CMB.
- Observations were performed at the Amundsen-Scott South Pole research station over two years.
Main Results:
- Successfully conducted polarization-sensitive observations of the CMB.
- Demonstrated the capability to detect CMB polarization, overcoming previous limitations.
- Collected data on CMB polarization fluctuations across angular scales.
Conclusions:
- The DASI instrument has successfully measured CMB polarization.
- These measurements represent a significant advancement in observational cosmology.
- The findings pave the way for deeper understanding of the Universe's fundamental properties.
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