SPIRE point source photometry: within the Herschel interactive processing environment (HIPE)

Autor: Nicolas Laporte, Dave Shupe, George J. Bendo, Kevin Xu, Luca Conversi, Andreas Papageorgiou, Chris Pearson, Tanya Lim, Terry Jin, Anthony J. Smith, Bernhard Schulz, Darren Dowell, C. North, Matthew Joseph Griffin
Rok vydání: 2013
Předmět:
Zdroj: Experimental Astronomy. 37:175-194
ISSN: 1572-9508
0922-6435
Popis: The different algorithms appropriate for point source photometry on data from the SPIRE instrument on-board the Herschel Space Observatory, within the Herschel Interactive Processing Environment (HIPE) are compared. Point source photometry of a large ensemble of standard calibration stars and dark sky observations is carried out using the 4 major methods within HIPE: SUSSEXtractor, DAOphot, the SPIRE Timeline Fitter and simple Aperture Photometry. Colour corrections and effective beam areas as a function of the assumed source spectral index are also included to produce a large number of photometric measurements per individual target, in each of the 3 SPIRE bands (250, 350, 500μm), to examine both the accuracy and repeatability of each of the 4 algorithms. It is concluded that for flux densities down to the level of 30mJy that the SPIRE Timeline Fitter is the method of choice. However, at least in the 250 and 350μm bands, all 4 methods provide photometric repeatability better than a few percent down to at approximately 100mJy. The DAOphot method appears in many cases to have a systematic offset of ∼8 % in all SPIRE bands which may be indicative of a sub-optimal aperture correction. In general, aperture photometry is the least reliable method, i.e. largest scatter between observations, especially in the longest wavelength band. At the faintest fluxes
Databáze: OpenAIRE
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