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arXiv · 1209.3792

A new method to detect solar-like oscillations at very low S/N using statistical significance testing

Mikkel N. Lund·William J. Chaplin·Hans Kjeldsen
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Abstract

We introduce a new method to detect solar-like oscillations in frequency power spectra of stellar observations, under conditions of very low signal to noise. The Moving-Windowed-Power-Search, or MWPS, searches the power spectrum for signatures of excess power, over and above slowly varying (in frequency) background contributions from stellar granulation and shot or instrumental noise. We adopt a false-alarm approach (Chaplin et al. 2011) to ascertain whether flagged excess power, which is consistent with the excess expected from solar-like oscillations, is hard to explain by chance alone (and hence a candidate detection). We apply the method to solar photometry data, whose quality was systematically degraded to test the performance of the MWPS at low signal-to-noise ratios. We also compare the performance of the MWPS against the frequently applied power-spectrum-of-power-spectrum (PSxPS) detection method. The MWPS is found to outperform the PSxPS method.

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Mikkel N. Lund, William J. Chaplin, Hans Kjeldsen. 2012-09-17. A new method to detect solar-like oscillations at very low S/N using statistical significance testing. https://doi.org/10.1111/j.1365-2966.2012.22098.x

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