Validating Stellar Abundance Measurements from Multi-Resolution Spectroscopy
arXiv:2303.04098 · doi:10.3847/1538-4365/acd37b
Abstract
Large-scale surveys will provide spectroscopy for 50 million resolved stars in the Milky Way and Local Group. However, these data will have a high degree of heterogeneity and most will be low-resolution (), posing challenges to measuring consistent and reliable stellar labels. Here, we introduce a framework for identifying and remedying these issues. By simultaneously fitting the full spectrum and Gaia photometry with the Payne, we measure 40 abundances for 8 red giants in M15. From degraded quality Keck/HIRES spectra, we evaluate trends with resolution and S/N and find that (i) 20 abundances are recovered consistently within 0.1 dex agreement and with 0.05-0.15~dex systematic uncertainties from ; (ii) for 9 elements (C, Mg, Ca, Sc, Ti, Fe, Ni, Y, Nd), this systematic precision and accuracy extends down to ; and (iii) while most elements do not exhibit strong S/N-dependent systematics, there are non-negligible biases for 4 elements (C, Mg, Ca, and Dy) below pixel. We compare statistical uncertainties from MCMC sampling to the easier-to-compute Cramér-Rao bounds and find that they agree for 75% of elements, indicating the latter to be a reliable and faster way to estimate uncertainties. Our analysis illustrates the great promise of low-resolution spectroscopy for stellar chemical abundance work, and ongoing improvements to stellar models (e.g., 3D-NLTE physics) will only further extend its viability to more elements and to higher precision and accuracy.
46 pages, 26 figures, submitted to ApJS. Comments welcome!
References in corpus (27)
- Array Programming with NumPy
- The NumPy array: a structure for efficient numerical computation
- Modules for Experiments in Stellar Astrophysics (MESA)
- The James Webb Space Telescope
- The GALAH Survey: Scientific Motivation
- APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South
- Accurate distances to Galactic globular clusters through a combination of Gaia EDR3, HST and literature data
- Modern stellar spectroscopy caveats
- 4MOST: Project overview and information for the First Call for Proposals
- Gaia-ESO Survey: The analysis of high-resolution UVES spectra of FGK-type stars
- NLTE abundances of Mn in a sample of metal-poor stars
- A non-LTE study of neutral and singly-ionized calcium in late-type stars
- Multi-Element Abundance Measurements from Medium-Resolution Spectra. II. Catalog of Stars in Milky Way Dwarf Satellite Galaxies
- Multi-Element Abundance Measurements from Medium-Resolution Spectra. IV. Alpha Element Distributions in Milky Way Dwarf Satellite Galaxies
- Exploring Anticorrelations and Light Element Variations in Northern Globular Clusters Observed by the APOGEE Survey
- VLT/UVES Spectroscopy of Individual Stars in Three Globular Clusters in the Fornax Dwarf Spheroidal Galaxy
- Stellar Chemical Abundances: In Pursuit of the Highest Achievable Precision
- A homogeneous analysis of globular clusters from the APOGEE survey with the BACCHUS code. I. The Northern clusters
- Signatures of unresolved binaries in stellar spectra: implications for spectral fitting
- A Comparison of Stellar Elemental Abundance Techniques and Measurements
- Manganese Abundances in Cluster and Field Stars
- Neutron-capture elements in the metal-poor globular cluster M15
- Measuring 14 elemental abundances with R=1,800 LAMOST spectra
- Prospects for Measuring Abundances of >20 Elements with Low-resolution Stellar Spectra
- Catalog of Chromium, Cobalt, and Nickel Abundances in Globular Clusters and Dwarf Galaxies
- Forecasting Chemical Abundance Precision for Extragalactic Stellar Archaeology
- NLTE modelling of integrated light spectra. Abundances of barium, magnesium, and manganese in a metal-poor globular cluster