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تسجيل مستخدم جديدThe ASTRODEEP-GS43 catalogue: new photometry and redshifts for the CANDELS GOODS-South field
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We present ASTRODEEP-GS43, a new multiwavelength photometric catalogue of the GOODS-South field, which builds and improves upon the previously released CANDELS catalogue. We provide photometric fluxes and corresponding uncertainties in 43 optical and infrared bands (25 wide and 18 medium filters), as well as photometric redshifts and physical properties of the 34930 CANDELS $H$-detected objects, plus an additional sample of 178 $H$-dropout sources, of which 173 are $Ks$-detected and 5 IRAC-detected. We keep the CANDELS photometry in 7 bands (CTIO $U$, Hubble Space Telescope WFC3 and ISAAC-$K$), and measure from scratch the fluxes in the other 36 (VIMOS, HST ACS, HAWK-I $Ks$, Spitzer IRAC, and 23 from Subaru SuprimeCAM and Magellan-Baade Fourstar) with state-of-the-art techniques of template-fitting. We then compute new photometric redshifts with three different software tools, and take the median value as best estimate. We finally evaluate new physical parameters from SED fitting, comparing them to previously published ones. Comparing to a sample of 3931 high quality spectroscopic redshifts, for the new photo-$z$s we obtain a normalized median absolute deviation (NMAD) of 0.015 with 3.01$%$ of outliers (0.011, 0.22$%$ on the bright end at $I814$<22.5), similarly to the best available published samples of photometric redshifts, such as the COSMOS UltraVISTA catalogue. The ASTRODEEP-GS43 results are in qualitative agreement with previously published catalogues of the GOODS-South field, improving on them particularly in terms of SED sampling and photometric redshift estimates. The catalogue is available for download from the Astrodeep website.
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