J/ApJS/230/9 Improved multi-band photometry from SERVS (Nyland+, 2017) ================================================================================ An application of multi-band forced photometry to one square degree of SERVS: accurate photometric redshifts and implications for future science. Nyland K., Lacy M., Sajina A., Pforr J., Farrah D., Wilson G., Surace J., Haussler B., Vaccari M., Jarvis M. =2017ApJS..230....9N (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Photometry, infrared ; Photometry, ugriz ; Surveys Keywords: catalogs; Galaxies: evolution; methods: data analysis; surveys; techniques: image processing Abstract: We apply The Tractor image modeling code to improve upon existing multi-band photometry for the Spitzer Extragalactic Representative Volume Survey (SERVS). SERVS consists of post-cryogenic Spitzer observations at 3.6 and 4.5{mu}m over five well-studied deep fields spanning 18deg^2^. In concert with data from ground-based near-infrared (NIR) and optical surveys, SERVS aims to provide a census of the properties of massive galaxies out to z~5. To accomplish this, we are using The Tractor to perform "forced photometry." This technique employs prior measurements of source positions and surface brightness profiles from a high-resolution fiducial band from the VISTA Deep Extragalactic Observations survey to model and fit the fluxes at lower-resolution bands. We discuss our implementation of The Tractor over a square-degree test region within the XMM Large Scale Structure field with deep imaging in 12 NIR/optical bands. Our new multi-band source catalogs offer a number of advantages over traditional position-matched catalogs, including (G1) consistent source cross-identification between bands, (2) de-blending of sources that are clearly resolved in the fiducial band but blended in the lower resolution SERVS data, (3) a higher source detection fraction in each band, (4) a larger number of candidate galaxies in the redshift range 5