Fluorine Abundances in the Globular Cluster M 4

Abstract

We present chemical abundances for the elements carbon, sodium, and fluorine in 15 red giants of the globular cluster M 4, as well as six red giants of the globular cluster $\omega$ Centauri. The chemical abundances were calculated in LTE via spectral synthesis. The spectra analyzed are high-resolution spectra obtained in the near-infrared region around $\lambda$2.3$\mu$m with the Phoenix spectrograph on the 8.1m Gemini South Telescope, the IGRINS spectrograph on the McDonald Observatory 2.7m Telescope, and the CRIRES spectrograph on the ESO 8.2m Very Large Telescope. The results indicate a significant reduction in the fluorine abundances when compared to previous values from the literature for M 4 and $\omega$ Centauri, due to a downward revision in the excitation potentials of the HF(1-0) R9 line used in the analysis. The fluorine abundances obtained for the M 4 red giants are found to be anti-correlated with those of Na, following the typical pattern of abundance variations seen in globular clusters between distinct stellar populations. In M 4, as the Na abundance increases by $\sim$+0.4 dex, the F abundance decreases by $\sim$-0.2 dex. A comparison with abundance predictions from two sets of stellar evolution models finds that the models predict somewhat less F depletion ($\sim$-0.1 dex) for the same increase of +0.4 dex in Na.

References in corpus (32)

• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
• Na-O Anticorrelation and HB. VIII. Proton-capture elements and metallicities in 17 globular clusters from UVES spectra
• A new implementation of the infrared flux method using the 2MASS catalogue
• Chemical Abundances for 855 Giants in the Globular Cluster Omega Centauri (NGC 5139)
• Thermohaline instability and rotation-induced mixing. III - Grid of stellar models and asymptotic asteroseismic quantities from the pre-main sequence up to the AGB for low- and intermediate-mass stars at various metallicities
• Star-to-Star Abundance Variations among Bright Giants in the Mildly Metal-Poor Globular Cluster M4
• The effective temperature scale of FGK stars. I. Determination of temperatures and angular diameters with the infrared flux method
• Chemical similarities between Galactic bulge and local thick disk red giants: O, Na, Mg, Al, Si, Ca and Ti
• Abundances in Stars from the Red Giant Branch Tip to Near the Main Sequence Turn Off in M71: III. Abundance Ratios
• Evolution and Nucleosynthesis of Extremely Metal Poor & Metal-Free Low- and Intermediate-Mass Stars I: Stellar Yield Tables and the CEMPs
• Chemical Abundances in Field Red Giants from High-Resolution H-Band Spectra using the APOGEE Spectral Linelist
• Modelling self-pollution of globular clusters from AGB stars
• Abundance Analysis of Turn-Off and Early Subgiant Stars in the Globular Cluster 47 Tuc (NGC 104)
• Sodium-Oxygen anticorrelation among Horizontal Branch Stars in the Globular Cluster M4
• The C+N+O abundance of Omega Centauri giant stars: implications on the chemical enrichment scenario and the relative ages of different stellar populations
• Fluorine Abundance Variations in Red Giants of the Globular Cluster M4 and Early-Cluster Chemical Pollution
• Fluorine and Sodium in C-rich low-metallicity stars
• Carbon in Red Giants in Globular Clusters and Dwarf Spheroidal Galaxies
• The extreme chemistry of multiple stellar populations in the metal-poor globular cluster NGC 4833
• Fluorine Abundances in the Large Magellanic Cloud and Omega Centauri: Evidence for Neutrino Nucleosynthesis?
• Chemical abundances in giants stars of the tidally disrupted globular cluster NGC 6712 from high-resolution infrared spectroscopy
• Chemical abundances in the multiple sub-giant branch of 47 Tucanae: insights on its faint sub-giant branch component
• CNO and F abundances in the globular cluster M22 (NGC 6656)
• The Chemical Evolution of Fluorine in the Bulge - High-resolution K-band spectra of giants in three fields
• Fluorine in the solar neighborhood - is it all produced in AGB-stars?
• Fluorine variations in the globular cluster NGC 6656 (M22): implications for internal enrichment timescales
• Fluorine Abundances of Galactic Low-Metallicity Giants
• Abundances of C, N, Sr and Ba on the red giant branch of omega Centauri
• Fluorine abundances and the puzzle of globular cluster chemical history
• Revisited fluorine abundances in the globular cluster M22 (NGC 6656)
• On the AGB stars of M 4: A robust disagreement between spectroscopic observations and theory

Cited by in corpus (10)

• Fluorine in the solar neighborhood: modelling the Galactic thick and thin discs
• Fluorine in the solar neighbourhood: the need for several cosmic sources
• Constraining $\nu$-Process Production of Fluorine through Cosmic Ray Nucleosynthesis
• Fluorine Abundances in the Galactic Disk
• M Giants with IGRINS II. Chemical Evolution of Fluorine at High Metallicities
• Detection of fluorine in hot Extreme Helium Stars
• Exploring fluorine chemical evolution in the Galactic disk: the open cluster perspective
• IGRINS RV: A Precision RV Pipeline for IGRINS Using Modified Forward Modeling in the Near-Infrared
• Robust statistical tools for identifying multiple stellar populations in globular clusters in the presence of measurement errors. A case study: NGC 2808
• The CUBES Science Case