1303.7408 (G. Belanger)

On Detecting Transients    [PDF]

G. Belanger

Transient phenomena are interesting and potentially highly revealing of details about the processes under observation and study that could otherwise go unnoticed. It is therefore important to maximise the sensitivity of the method used to identify such events. In this article we present a general procedure based on the use of the likelihood function for identifying transients that is particularly suited for real-time applications because it requires no grouping or pre-processing of the data. The method is optimal in the sense that all the information that is available in the data is used in the statistical decision making process, and is suitable for a wide range of applications. We here consider those most common in astrophysics which involve searching for transient sources, events or features in images, time series, energy spectra and power spectra, and demonstrate the use of the method in the cases of a transient in a time series or in a power spectrum. We derive a fit statistic that is ideal for fitting arbitrarily shaped models to a power density distribution which is of general interest in all applications involving periodogram analysis.

View original: http://arxiv.org/abs/1303.7408