Ultimate — Home

The ULTIMATE deblending project will eventually deliver a 70+ bands UV–to–Radio multiwavelength catalog for the several JWST deep fields (starting with PRIMER–COSMOS and PRIMER–UDS). It is built on deep JWST/NIRCam and MIRI imaging and harmonised with extensive ancillary data from HST (ACS/WFC3), Subaru/HSC, CFHT/MegaCam, VISTA/VIRCAM, UKIRT/UKIDSS, Magellan/Fourstar, Spitzer/IRAC, Spitzer/MIPS, Herschel, SCUBA-2, VLA, and MeerKAT. The catalog provides uniform, deblended photometry suitable for robust colours and SED modelling across both fields. See the Data page for the detailed band list and data release.

As shown in Fig.1, the coverage of the Ultimate survey is 286.9 arcmin² in PRIMER-COSMOS and 287.6 arcmin² in PRIMER-COSMOS. Our current data release include a 50-band UV to MIR catalog. The inclusion of low-resolution ground-based data improves the accuracy of photo-zs by ~40%, and reduces outlier fraction by ~60%. In the future data releases, we will further provide the deblended FIR to Radio photometry and new JWST observations.

PRIMER-COSMOS and PRIMER-UDS footprints — **Fig.1** The coverage of the key surveys within PRIMER-COSMOS (left panel) and PRIMER-UDS (right panel). The background grayscale image presents the 3σ limiting depth (in 0.2” diameter apertures) for point sources of the stacked JWST/NIRCam image, which is used for source detection. The blue, orange, and red lines show the coverage of the HST data from the CANDELS survey (Galametz et al. 2013; Nayyeri et al. 2017), the JWST/MIRI data taken with the PRIMER survey (Dunlop et al. 2021), and the deep SCUBA-2 450um and 850um data from the STUDIES survey (Gao et al. 2024).

Citations

If you use data from the ULTIMATE deblending project in a published work, please cite Wang+25 and Sun+26.
If you use the FIR to Radio photometry from the ULTIMATE deblending project, please also cite a forthcoming paper (H.Sun et al. in preparation)