Multitaper testing of spectral lines and the detection of the solar rotation frequency and its harmonics
Abstract:We develop statistical testing methodology for closely spaced spectral lines based on multitaper spectrum estimates and apply it to a time series of solar magnetic field magnitude data recorded by the Ulysses spacecraft. The test is formulated through complex-valued weighted least squares. Using this test in combination with the test for well-separated lines, we can accurately detect the solar equatorial rotation frequency of the sun, and its harmonics, from data recorded by Ulysses's magnetometer at solar mid-latitudes; this is a potentially important result for solar physicists, since it has implications for the structure and dynamics of magnetic fields in the solar corona.
Document Type: Original Article
Affiliations: Imperial College of Science, Technology and Medicine, London, UK
Publication date: January 1, 1999