HOW ACCURATE ARE INFRARED LUMINOSITIES FROM MONOCHROMATIC PHOTOMETRIC EXTRAPOLATION?

Abstract

Template-based extrapolations from only one photometric band can be a cost-effective method to estimate the total infrared (IR) luminosities ( ) of galaxies. By utilizing multi-wavelength data that covers across 0.35–500 μ m in GOODS-North and GOODS-South fields, we investigate the accuracy of this monochromatic extrapolated based on three IR spectral energy distribution (SED) templates out to . We find that the Chary & Elbaz template provides the best estimate of in Herschel /Photodetector Array Camera and Spectrometer (PACS) bands, while the Dale & Helou template performs best in Herschel /Spectral and Photometric Imaging Receiver (SPIRE) bands. To estimate , we suggest that extrapolations from the available longest wavelength PACS band based on the Chary & Elbaz template can be a good estimator. Moreover, if the PACS measurement is unavailable, extrapolations from SPIRE observations but based on the Dale & Helou template can also provide a statistically unbiased estimate for galaxies at . The emission with a rest-frame 10–100 μ m range of IR SED can be well described by all three templates, but only the Dale & Helou template shows a nearly unbiased estimate of the emission of the rest-frame submillimeter part.