How accurate are infrared luminosities from monochromatic photometric
  extrapolation?
  Template-based extrapolations from only one photometric band can be a
cost-effective method to estimate the total infrared (IR) luminosities
($L_{\mathrm{IR}}$) of galaxies. By utilizing multi-wavelength data that covers
across 0.35--500\,$\mathrm{\mu m}$ in GOODS-North and GOODS-South fields, we
investigate the accuracy of this monochromatic extrapolated $L_{\mathrm{IR}}$
based on three IR spectral energy distribution (SED) templates
(\citealt[CE01]{Chary2001}; \citealt[DH02]{Dale2002};
\citealt[W08]{Wuyts2008a}) out to $z\sim 3.5$. We find that the CE01 template
provides the best estimate of $L_{\mathrm{IR}}$ in {\it Herschel}/PACS bands,
while the DH02 template performs best in {\it Herschel}/SPIRE bands. To
estimate $L_{\mathrm{IR}}$, we suggest that extrapolations from the available
longest wavelength PACS band based on the CE01 template can be a good
estimator. Moreover, if PACS measurement is unavailable, extrapolations from
SPIRE observations but based on the \cite{Dale2002} template can also provide a
statistically unbiased estimate for galaxies at $z\lesssim 2$. The emission of
rest-frame 10--100\,$\mathrm{\mu m}$ range of IR SED can be well described by
all the three templates, but only the DH02 template shows nearly unbiased
estimate of the emission of the rest-frame submillimeter part.
