Improving the identification of high-z Herschel sources with position priors and optical/NIR and FIR/mm photometric redshifts
We present preliminary results about the detection of high redshift (U)LIRGs in the Bullet cluster field by the PACS and SPIRE instruments within the Herschel Lensing Survey (HLS) Program. We describe in detail a photometric procedure designed to recover robust fluxes and deblend faint Herschel sources near the confusion noise. The method is based on the use of the positions of Spitzer/MIPS 24 μm sources as priors. Our catalogs are able to reliably (5σ) recover galaxies with fluxes above 6 and 10 mJy in the PACS 100 and 160 μm channels, respectively, and 12 to 18 mJy in the SPIRE bands. We also obtain spectral energy distributions covering the optical through the far-infrared/millimeter spectral ranges of all the Herschel detected sources, and analyze them to obtain independent estimations of the photometric redshift based on either stellar population or dust emission models. We exemplify the potential of the combined use of Spitzer position priors plus independent optical and IR photometric redshifts to robustly assign optical/NIR counterparts to the sources detected by Herschel and other (sub-)mm instruments.
Additional Information© 2010 ESO. Received 31 March 2010; Accepted 6 May 2010; Published online 16 July 2010. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. This work is based in part on observations made with Spitzer, operated by JPL/Caltech. We thank the AzTEC Team for letting us use their data. P.G.P.-G. acknowledges support from grants AYA 2006–02358, AYA 2006–15698–C02–02, and CSD2006-00070, and the Ramón y Cajal Program, all financed by the Spanish Government and/or the European Union.
Published - PerezGonzalez2010p11851Astron_Astrophys.pdf