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NGC 2420 is a $\sim$2 Gyr-old well-populated open cluster that lies about 2kpc beyond the solar circle, in the general direction of the Galacticanti-center. Most previous abundance studies have found this cluster to bemildly metal-poor, but with a large scatter in the obtained metallicities forthis open cluster. Detailed chemical abundance distributions are derived for 12red-giant members of NGC 2420 via a manual abundance analysis ofhigh-resolution (R = 22,500) near-infrared ($\lambda$1.5 - 1.7$\mu$m) spectraobtained from the Apache Point Observatory Galactic Evolution Experiment(APOGEE) survey. The sample analyzed contains 6 stars that are identified asmembers of the first-ascent red giant branch (RGB), as well as 6 members of thered clump (RC). We find small scatter in the star-to-star abundances in NGC2420, with a mean cluster abundance of [Fe/H] = -0.16 $\pm$ 0.04 for the 12 redgiants. The internal abundance dispersion for all elements (C, N, O, Na, Mg,Al, Si, K, Ca, Ti, V, Cr, Mn, Co and Ni) is also very small ($\sim$0.03 - 0.06dex), indicating a uniform cluster abundance distribution within theuncertainties. NGC 2420 is one of the clusters used to calibrate the APOGEEStellar Parameter and Chemical Abundance Pipeline (ASPCAP). The results fromthis manual analysis compare well with ASPCAP abundances for most of theelements studied, although for Na, Al and V there are more significant offsets.No evidence of extra-mixing at the RGB luminosity bump is found in the $^{12}$Cand $^{14}$N abundances from the pre-luminosity-bump RGB stars in comparison tothe post-He core-flash RC stars.

Chemical Abundances in a Sample of Red Giants in the Open Cluster NGC 2420 from APOGEE