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Baade's window (BW) is one of the most observed Galactic bulge fields interms of chemical abundances. Due to its low and homogeneous interstellarabsorption it is considered as a calibration field for Galactic bulge studies.In the era of large spectroscopic surveys, calibration fields such as BW arenecessary to cross calibrate the stellar parameters and individual abundancesof the APOGEE survey. We use the APOGEE BW stars to derive their metallicitydistribution function (MDF) and individual abundances, for $\alpha$- andiron-peak elements of the APOGEE ASPCAP pipeline (DR13), as well as the agedistribution for stars in BW. We determine the MDF of APOGEE stars in BW andfind a remarkable agreement with that of the Gaia-ESO survey (GES). Bothexhibit a clear bimodal distribution. We also find that the Mg-metallicityplanes of both surveys agree well, except for the metal-rich part ([Fe/H]>0.1), where APOGEE finds systematically higher Mg abundances with respect tothe GES. The ages based on the [C/N] ratio reveal a bimodal age distribution,with a major old population at 10 Gyr, with a decreasing tail towards youngerstars. A comparison between APOGEE estimates and stellar parameters, and thosedetermined by other sources reveals detectable systematic offsets, inparticular for spectroscopic surface gravity estimates. In general, we find agood agreement between individual abundances of O, Na, Mg, Al, Si, K, Ca, Cr,Mn, Co, and Ni from APOGEE with that of literature values. We have shown thatin general APOGEE data show a good agreement in terms of MDF and individualchemical abundances with respect to literature works. Using the [C/N] ration wefound a significant fraction of young stars in BW which is in agreement withthe model of Haywood et al. (2016).

Baade's window with APOGEE: Metallicities, ages and chemical abundances