SIMBAD references

We acquired near-infrared spectra of the Oort cloud comet C/2012 F6 (Lemmon) at three different heliocentric distances (R_h) during the comet's 2013 perihelion passage, providing a comprehensive measure of the outgassing behavior of parent volatiles and cosmogonic indicators. Our observations were performed pre-perihelion at R_h= 1.2 AU with CRIRES (on 2013 February 2 and 4), and post-perihelion at R_h= 0.75 AU with CSHELL (on March 31 and April 1) and R_h= 1.74 AU with NIRSPEC (on June 20). We detected 10 volatile species (H₂O, OH* prompt emission, C₂H₆, CH₃OH, H₂CO, HCN, CO, CH₄, NH₃, and NH₂), and obtained upper limits for two others (C₂H₂ and HDO). One-dimensional spatial profiles displayed different distributions for some volatiles, confirming either the existence of polar and apolar ices, or of chemically distinct active vents in the nucleus. The ortho-para ratio for water was 3.31±0.33 (weighted mean of CRIRES and NIRSPEC results), implying a spin temperature >37 K at the 95% confidence limit. Our (3σ) upper limit for HDO corresponds to D/H < 2.45x10^–3 (i.e., <16 Vienna Standard Mean Ocean Water, VSMOW). At R_h= 1.2 AU (CRIRES), the production rate for water was Q(H₂O) = 1.9±0.1x10²⁹/s and its rotational temperature was T_rot∼ 69 K. At R_h= 0.75 AU (CSHELL), we measured Q(H₂O) = 4.6±0.6x10²⁹/s and T_rot= 80 K on March 31, and 6.6±0.9x10²⁹/s and T_rot= 100 K on April 1. At R_h= 1.74 AU (NIRSPEC), we obtained Q(H₂O) = 1.1±0.1x10²⁹/s and T_rot∼ 50 K. The measured volatile abundance ratios classify comet C/2012 F6 as rather depleted in C₂H₆ and CH₃OH, while HCN, CH₄, and CO displayed abundances close to their median values found among comets. H₂CO was the only volatile showing a relative enhancement. The relative paucity of C₂H₆and CH₃OH (with respect to H₂O) suggests formation within warm regions of the nebula. However, the normal abundance of HCN and hypervolatiles CH₄and CO, and the enhancement of H₂CO, may indicate a possible heterogeneous nucleus of comet C/2012 F6 (Lemmon), possibly as a result of radial mixing within the protoplanetary disk.