On the likelihood-ratio test applied in asteroseismology for mode identification

TL;DR

This paper evaluates the effectiveness of the likelihood-ratio test in asteroseismology for identifying oscillation modes, especially under low signal-to-noise conditions, using simulated data.

Contribution

It provides a statistical analysis of the likelihood-ratio test's accuracy in mode identification and defines its applicability limits based on signal-to-noise ratio.

Findings

Likelihood-ratio test is effective up to a certain magnitude.

The test's accuracy depends on signal-to-noise ratio.

Simulations show the test's limitations in low SNR scenarios.

Abstract

The identification of the solar-like oscillation modes, as measured by asteroseismology, is a necessary requirement in order to infer the physical properties of the interior of the stars. Difficulties occur when a large number of modes of oscillations with a low signal-to-noise ratio are observed. In those cases, it is of common use to apply a likelihood-ratio test to discriminate between the possible scenarios. We present here a statistical analysis of the likelihood-ratio test and discuss its accuracy to identify the correct modes. We use the AsteroFLAG artificial stars, simulated over a range of magnitude, inclination angle, and rotation rate. We show that the likelihood-ratio test is appropriate up to a certain magnitude (signal-to-noise ratio).