Cosmic Origin of Fluorine : The Open Cluster Perspective

• The study of open clusters enables the determination of accurate values for a multitude of variables, as the stars within them are expected to have a con­ sistent age, distance, and chemical content. Consequently, they are optimal for elucidating the cosmic genesis of complex elements, such as Fluorine. The objective of this project is to analyze the abundance of Fluorine in 13 open clusters, in which we have observed 31 stars in total. Additionally, eight field stars have been included in the analysis. This is the most exhaus­ tive and homogeneous database to date, which has been designed to derive Fluorine abundances across the galactic disk. While the principal objective is to comprehend the distribution of galactic Fluorine, the abundances of Cerium are also derived in order to elucidate the interrelationship between Fluorine and s­process elements. In addition to the aforementioned elements, the abundances of Magnesium are derived in order to facilitate the categorization of the field stars in the low­?­ and high­? sequences, which is of importance for our method of determining stellar parameters. The abundances of Fluorine and Cerium are compared with metallicities, ages, and galactocentric distances in order to provide valuable insights into the origin of these elements through galactic chemical evolution models. The spectra were collected using the high­resolution GIANO­B instrument, which operates at the 3.58­meter Galileo National Telescope in the near­ infrared wavelength range. The Python version of Spectroscopy Made Easy was employed to analyze the spectra and derive stellar parameters as well as abundances. The H­band region was used to derive stellar parameters. The stellar parameters were obtained by analyzing the OH, CN, and CO molecular lines and band heads in addition to Fe I lines. K­band HF lines (?? 2.28, 2.33 ?m), three K­band Mg I lines (?? 2.10, 2.11, 2.15 ?m), and two H­band Ce II lines (?? 1.66, and 1.71 ?m) were used to derive Fluorine, Magnesium, and Cerium abundances, respectively. When compared with theoretical models, the observed trends suggest that both asymptotic giant branch stars and massive stars—including a proportion of fast rotators that are likely to increase with declining metallicity—are necessary to explain the cosmic origin of Fluorine. 

Ämnesord

NATURVETENSKAP  -- Fysik -- Astronomi, astrofysik och kosmologi (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Astronomy, Astrophysics and Cosmology (hsv//eng)

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