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arXiv · 1110.0960

Photometry and Photometric Redshift catalogs for the Lockman Hole Deep Field

S. Fotopoulou·M. Salvato·G. Hasinger·E. Rovilos·M. Brusa·E. Egami·D. Lutz·V. Burwitz·J. H. Huang·D. Rigopoulou·M. Vaccari
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Abstract

We present broad band photometry and photometric redshifts for 187611 sources located in ~0.5deg^2 in the Lockman Hole area. The catalog includes 389 X-ray detected sources identified with the very deep XMM-Newton observations available for an area of 0.2 deg^2. The source detection was performed on the Rc, z' and B band images and the available photometry is spanning from the far ultraviolet to the mid infrared, reaching in the best case scenario 21 bands. Astrometry corrections and photometric cross-calibrations over the entire dataset allowed the computation of accurate photometric redshifts. Special treatment is undertaken for the X-ray sources, the majority of which is active galactic nuclei. Comparing the photometric redshifts to the available spectroscopic redshifts we achieve for normal galaxies an accuracy of \sigma_{\Delta z/(1+z)}=0.036, with 12.7% outliers, while for the X-ray detected sources the accuracy is \sigma_{\Delta z/(1+z)}=0.069, with 18.3% outliers, where the outliers are defined as sources with |z_{phot}-z_{spec}|>0.15 (1+z_{spec})}. These results are a significant improvement over the previously available photometric redshifts for normal galaxies in the Lockman Hole, while it is the first time that photometric redshifts are computed and made public for AGN for this field.

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S. Fotopoulou, M. Salvato, G. Hasinger, E. Rovilos, M. Brusa, E. Egami, D. Lutz, V. Burwitz, J. H. Huang, D. Rigopoulou, M. Vaccari. 2011-10-05. Photometry and Photometric Redshift catalogs for the Lockman Hole Deep Field. https://doi.org/10.1088/0067-0049%2F198%2F1%2F1

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