NGC 2420 is a \sim 2 Gyr-old well-populated open cluster that lies about 2 kpc beyond the solar circle , in the general direction of the Galactic anti-center .
Most previous abundance studies have found this cluster to be mildly metal-poor , but with a large scatter in the obtained metallicities for this open cluster .
Detailed chemical abundance distributions are derived for 12 red-giant members of NGC 2420 via a manual abundance analysis of high-resolution ( R = 22,500 ) near-infrared ( \lambda 1.5 - 1.7 \mu m ) spectra obtained from the Apache Point Observatory Galactic Evolution Experiment ( APOGEE ) survey .
The sample analyzed contains 6 stars that are identified as members of the first-ascent red giant branch ( RGB ) , as well as 6 members of the red clump ( RC ) .
We find small scatter in the star-to-star abundances in NGC 2420 , with a mean cluster abundance of [ Fe/H ] = -0.16 \pm 0.04 for the 12 red giants .
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 - 0.06 dex ) , indicating a uniform cluster abundance distribution within the uncertainties .
NGC 2420 is one of the clusters used to calibrate the APOGEE Stellar Parameter and Chemical Abundance Pipeline ( ASPCAP ) .
The results from this manual analysis compare well with ASPCAP abundances for most of the elements 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 } C and ^ { 14 } N abundances from the pre-luminosity-bump RGB stars in comparison to the post-He core-flash RC stars .