Guillaume Leleu (LAM CNRS), Anne-Laure Méalier, Dominique Benielli, Jean-Paul Baluteau, Christian Surace, Trevor R. Fulton, Peter Davis-Imhof, Edward Polehampton, Didier Vibert.
The Herschel Space Observatory is a cornerstone mission of the European Space Agency for astronomical observations in the far-infrared and sub-millimeter wavelength range (60 - 670 microns) and has been launched in May 2009 with three instruments onboard : SPIRE, PACS, HIFI. This paper focuses on the development and the statistical analysis of two phenomena treated by the pipeline through both tasks ClippingCorrection and Deglitching. Glitches have to be re-moved to avoid the introduction of unwanted artefacts in the spectral energy distribution across all wavelengths. Clipped signals in the time-line are problematic as they represent missed samples. If left uncorrected, missed or erroneous samples can lead to further difficulties in particular when the time-lines are converted into spectra.
The first level deglitching task of the spectrometer pipeline is based on Continuous Wavelet Decomposition. The detection part of this task has already been described in previous ADASS paper(1). This paper describes the new reconstructed method based on a adaptive algorithm using wavelet decomposition parameters. We also present statistic tool to analyse clipping and deglitching phenomena. The tool shows ratios and indicators that are calculated and plotted allowing visual monitoring. The various aggregated values give a synthetic graphical representation of the quality of the observation including Instrument and Telescope Temperatures behaviours.
This tool has been developed as a plug-in of the HIPE environment.
(1) Dominique Benielli and all , « The Herschel-SPIRE Imaging FTS Pipeline: Testing the Deglitching Modules » Astronomical Data Analysis Software and Systems XVIII ASP Conference Series, Vol.411, c 2009
Paper ID: P083