97 citations · 225 across the 16 of their papers we have counts for
16 papers
The Galactic Phosphorus Survey. I. Chemical Evolution across the Galactic Disk from 750 FGK Stars
Dionysios Gakis, Keith Hawkins, Zachary G. Maas +5
Phosphorus (P) is an odd- element produced primarily in massive stars and is also important for planetary chemistry as an element essential to life. However, its evolution over…
Barium Stars Across the Milky Way: Probing Their Origins via the GALAH Survey
Jaden Levine, Catherine Manea, Keith Hawkins +4
Barium stars are unusually enriched in barium ([Ba/Fe] >= 1.0 dex) and not predicted by current Galactic chemical evolution models. Previous observations of barium stars have found…
Exploring the History of Stellar Mergers with Chemistry: Examining the Origins of Massive -Enriched Stars using Carbon Isotope Ratios
Zachary G. Maas, Keith Hawkins, Jeffrey M. Gerber +2
Recently discovered massive -enriched (MAE) stars have surface chemistry consistent with members of the older thick disk Milky Way population but high masses ( 1.5 - 3 M$_…
High-resolution Elemental Abundance Measurements of Cool JWST Planet Hosts Using AutoSpecFit: An Application to the Sub-Neptune K2-18b's Host M dwarf
Neda Hejazi, Ian J. M. Crossfield, Diogo Souto +9
We present an in-depth, high-resolution spectroscopic analysis of the M dwarf K2-18 that hosts a sub-Neptune exoplanet in its habitable zone. We show our technique to accurately no…
Fluorine Abundances in Local Stellar Populations
K. E. Brady, C. A. Pilachowski, V. Grisoni +2
We present the first fluorine measurements in 12 normal giants belonging to the Galactic thin and thick disks using spectra obtained with the Phoenix infrared spectrometer on the 2…
On its way to the neutron star-white dwarf binary graveyard, IGR J16194-2810, a first ascent M giant X-ray binary
K. H. Hinkle, F. C. Fekel, O. Straniero +5
A single-lined spectroscopic orbit for the M giant in the X-ray binary IGR J16194-2810 is determined from a time-series of optical spectra. The spectroscopic orbital period of 192.…
ELemental abundances of Planets and brown dwarfs Imaged around Stars (ELPIS): I. Potential Metal Enrichment of the Exoplanet AF Lep b and a Novel Retrieval Approach for Cloudy Self-luminous Atmospheres
Zhoujian Zhang, Paul Mollière, Keith Hawkins +10
AF Lep A+b is a remarkable planetary system hosting a gas-giant planet that has the lowest dynamical mass among directly imaged exoplanets. We present an in-depth analysis of the a…
The Galactic Distribution of Phosphorus: A Survey of 163 Disk and Halo Stars
Z. G. Maas, K. Hawkins, N. R. Hinkel +3
Phosphorus (P) is a critical element for life on Earth yet the cosmic production sites of P are relatively uncertain. To understand how P has evolved in the solar neighborhood, we…
A GALAH View of the Chemical Homogeneity and Ages of Stellar Strings Identified in Gaia
Catherine Manea, Keith Hawkins, Zachary G. Maas
The advent of Gaia has led to the discovery of nearly 300 elongated stellar associations (called `strings') spanning hundreds of parsecs in length and mere tens of parsecs in width…
linemake: An Atomic and Molecular Line List Generator
Vinicius M. Placco, Christopher Sneden, Ian U. Roederer +5
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…
The Galactic Chemical Evolution of Chlorine
Z. G. Maas, C. A. Pilachowski
We measured Cl abundances in 52 M giants with metallicities between -0.5 [Fe/H] 0.12. Abundances and atmospheric parameters were derived using infrared spectra from…
Phosphorus Abundances in the Hyades and Galactic Disk
Z. G. Maas, G. Cescutti, C. A. Pilachowski
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 m. High resolut…
Carbon Isotope Ratios in M10 Giants
Z. G. Maas, J. M. Gerber, Alex Deibel +1
We measured carbon abundances and the ratio in 31 giant branch stars with previous CN and CH band measurements that span -2.33 M …
Chlorine Isotope Ratios in M Giants
Z. G. Maas, C. A. Pilachowski
We have measured the chlorine isotope ratio in six M giant stars using HCl 1-0 P8 features at 3.7 microns with R 50,000 spectra from Phoenix on Gemini South. The average Cl…
Phosphorus Abundances in FGK Stars
Z. G. Maas, C. A. Pilachowski, G. Cescutti
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 t…
Chlorine Abundances in Cool Stars
Z. G. Maas, C. A. Pilachowski, K. Hinkle
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 HC…