Probing the IMF in the Early Universe -- Direct measurements in the Bo"otes I UFD with JWST/NIRCam

arXiv:2605.15069 · astro-ph.GA, astro-ph.SR · Submitted 2026-05-14 · Read on arXiv

astro-ph.GA, astro-ph.SR

Submitted: 2026-05-14

Updated: 2026-08-27

Comments: 28 pages, 17 figures, accepted for publication in ApJ

Code: https://github.com/Resolved-Stellar-Populations/starwave

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Metallicity — 16× in this paper · explained in 3 episodes
• Calibration — 8× in this paper · explained in 7 episodes
• Milky Way — 8× in this paper
• Abundance — 5× in this paper · explained in 1 episode
• Simulation-based Inference — 5× in this paper · explained in 2 episodes
• Forward modeling — 4× in this paper · explained in 2 episodes
• Initial Mass Function (IMF) — 3× in this paper · explained in 2 episodes
• Core — 2× in this paper · explained in 2 episodes
• Degeneracy — 2× in this paper · explained in 3 episodes
• Hilbert Space — 2× in this paper · explained in 2 episodes
• Accuracy — 1× in this paper · explained in 1 episode
• Aperture — 1× in this paper · explained in 1 episode
• Bayesian Inference — 1× in this paper · explained in 5 episodes
• Clustering — 1× in this paper · explained in 2 episodes
• Consistency — 1× in this paper · explained in 3 episodes
• Embeddings — 1× in this paper · explained in 2 episodes
• Hubble Space Telescope — 1× in this paper
• Hubble Ultra Deep Field — 1× in this paper
• Mass Segregation — 1× in this paper · explained in 2 episodes
• Population Synthesis — 1× in this paper · explained in 2 episodes
• SPECTROSCOPIC METALLICITY DISTRIBUTION FUNCTION — 1× in this paper
• Uncertainty Quantification — 1× in this paper · explained in 8 episodes

Sources

• The Keck/DEIMOS Stellar Archive: I. Uniform Velocities and Metallicities for 78 Milky Way Dwarf Galaxies and Globular Clusters
• Automatic Posterior Transformation for Likelihood-Free Inference
• Goodness-of-fit statistics for approximate Bayesian computation

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