2024/12/18 by E. Eftekhari, Eftekhari, E., A. Vazdekis +13
Mathematics · Medicine · Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics of Galaxies (astro-ph.GA) #Cluster (spacecraft) #Computer science #FOS: Physical sciences #Globular cluster #Infrared #Infrared spectroscopy #Mathematics #Medicine #Near-infrared spectroscopy #Optics #Physics #Point (geometry) #Population #Quantum mechanics #Spectroscopy #Star formation #Stars #Stellar population #Stellar, planetary, and galactic studies #Zero (linguistics) #Zero-point energy
paper · pdf · doi:10.48550/arxiv.2412.13587
openalex publication_date 2024/12/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Many recent studies have pointed out significant discrepancies between observations and models of stellar populations in the near-infrared (NIR). With current and future observing facilities being focused in this wavelength range, properly assessing and solving these issues is of utmost importance. Here, we present the first application of the extragalactic globular cluster (GC) near-infrared spectroscopy survey, and present evidence that these GCs reveal an age zero-point problem of stellar population synthesis (SPS) models. This problem has already been identified in the optical range for the GCs of the Milky Way. Such an issue arises when derived GC spectroscopic ages appear older than the Universe itself. We extend this discussion for the first time to the NIR, specifically using the Pa\rmβ line at 1.28~microns. We focus on the GCs of the nearby Centaurus~A galaxy using their NIR spectra. This work broadens our understanding of the age zero-point problem and emphasises the necessity to revisit and refine SPS models, especially in the NIR domain.