In this research note, we present linemake, an open-source atomic and molecular line list generator. Rather than a replacement for a number of well-established atomic and molecular spectral databases, linemake aims to be a lightweight, easy-to-use tool to generate formatted and curated lists suitable for spectral synthesis work. We encourage users of linemake to understand the sources of their transition data and cite them as appropriate in published work. We provide the code, line database, and an extensive list of literature references in a GitHub repository (https://github.com/vmplacco/linemake), which will be updated regularly as new data become available.

We measured phosphorus abundances in 22 FGK dwarfs and giants that span -0.55 < [Fe/H] < 0.2 using spectra obtained with the Phoenix high resolution infrared spectrometer on the Kitt Peak National Observatory Mayall 4m telescope, the Gemini South Telescope, and the Arcturus spectral atlas. We fit synthetic spectra to the P I feature at 10581Å to determine abundances for our sample. Our results are consistent with previously measured phosphorus abundances; the average [P/Fe] ratio measured in [Fe/H] bins of 0.2 dex for our stars are within ∼ 1 σ compared to averages from other IR phosphorus studies. Our study provides more evidence that models of chemical evolution using the results of theoretical yields are under producing phosphorus compared to the observed abundances. Our data better fit a chemical evolution model with phosphorus yields increased by a factor of 2.75 compared to models with unadjusted yields. We also found average [P/Si] = 0.02 ± 0.07 and [P/S] = 0.15 ± 0.15 for our sample, showing no significant deviations from the solar ratios for [P/Si] and [P/S] ratios.

We have measured phosphorus abundances in nine disk stars between -1 < [Fe/H] < -0.5 and in 12 members of the Hyades open cluster using two P I lines at 1.06 µm. High resolution infrared spectra were obtained using Phoenix on Gemini South and abundances were determined by comparing synthetic spectra to the observations. The average abundance for the dwarf stars in our Hyades sample was < [P/Fe] > = -0.01 ± 0.06 and < [P/Fe] > = 0.03 ± 0.03 dex for the three giants. The consistency suggests abundances derived using the 1.06 µm P I lines are not subjected to temperature or luminosity dependent systematic effects at high metallicities. Our [P/Fe] ratios measured in disk stars are consistent with chemical evolution models with P yields increased by a factor of 2.75. We find [P/O], [P/Mg], [P/Si] and [P/Ti] ratios are consistent with the solar ratio over a range of -1.0 < [Fe/H] < 0.2 with the [P/Si] ratio increasing by ∼ 0.1 -0.2 dex at the lowest [Fe/H] ratios. Finally, the evolution of [P/Fe] with age is similar to other α elements, providing evidence that P is produced at the same sites.

Chlorine abundances are reported in 15 evolved giants and one M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H 35 Cl at 3.69851 µm. The high resolution L-band spectra were observed using the Phoenix infrared spectrometer on the Kitt Peak Mayall 4m telescope. The average [ 35 Cl/Fe] abundance in stars with -0.72<[Fe/H]<0.20 is [ 35 Cl/Fe]=(-0.10±0.15) dex. The mean difference between the [ 35 Cl/Fe] ratios measured in our stars and chemical evolution model values is (0.16±0.15) dex. The [ 35 Cl/Ca] ratio has an offset of ∼0.35 dex above model predictions suggesting chemical evolution models are under producing Cl at the high metallicity range. Abundances of C, N, O, Si, and Ca were also measured in our spectral region and are consistent with F and G dwarfs. The Cl versus O abundances from our sample match Cl abundances measured in planetary nebula and H II regions. In one star where both H 35 Cl and H 37 Cl could be measured, a 35 Cl/ 37 Cl isotope ratio of 2.2±0.4 was found, consistent with values found in the Galactic ISM and predicted chemical evolution models.

We measured carbon abundances and the 12 C/ 13 C ratio in 31 giant branch stars with previous CN and CH band measurements that span -2.33 < M V < 0.18 in the globular cluster M10 (NGC 6254). Abundances were determined by comparing CO features at ∼ 2.3 µm and specifically the 13 CO bandhead at 2.37 µm, to synthetic spectra generated with MOOG. The observed spectra were obtained with GNIRS on Gemini North with a resolution of R ≈ 3500. The carbon abundances derived from the IR spectra agree with previous [C/Fe] measurements found using CN and CH features at the near-UV/blue wavelength range. We found an average carbon isotope ratio of 12 C/ 13 C = 5.10 +0.18 −0.17 for first generation stars (CN-normal; 13 stars total) and 12 C/ 13 C = 4.84 +0.27 −0.22 for second generation stars (CN-enhanced; 15 stars). We therefore find no statistically significant difference in 12 C/ 13 C ratio between stars in either population for the observed magnitude range. Finally, we created models of the expected carbon, nitrogen, and 12 C/ 13 C surface abundance evolution on the red giant branch due to thermohaline mixing using the MESA stellar evolution code. The efficiency of the thermohaline mixing must be increased to a factor of ≈ 60 to match [C/Fe] abundances, and by a factor of ≈ 666 to match 12 C/ 13 C ratios. We could not simultaneously fit the evolution of both carbon and the 12 C/ 13 C ratio with models using the same thermohaline efficiency parameter.