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Related papers: Fluorine Abundances in the Galactic Nuclear Star C…

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A non-LTE analysis of K I resonance lines at 7664.91 and 7698.97 A was carried out for 15 red giants belonging to three globular clusters of different metallicity (M 4, M 13, and M 15) along with two reference early-K giants (rho Boo and…

Solar and Stellar Astrophysics · Physics 2015-05-13 Y. Takeda , H. Kaneko , N. Matsumoto , S. Oshino , H. Ito , T. Shibuya

High-resolution, high signal-to-noise spectral data are presented for four young B-type stars lying towards the Galactic Centre. Determination of their atmospheric parameters from their absorption line profiles, and uvby photometric…

Astrophysics · Physics 2009-10-31 S. J. Smartt , K. A. Venn , P. L. Dufton , D. J. Lennon , W. R. J. Rolleston , F. P. Keenan

Chemical elements in the hot medium permeating early-type galaxies, groups, and clusters make them an excellent laboratory for studying metal enrichment and cycling processes in the largest scales of the universe. Here, we report the…

Astrophysics of Galaxies · Physics 2023-08-10 Kotaro Fukushima , Shogo B. Kobayashi , Kyoko Matsushita

Based on high-resolution spectra obtained with the MIKE spectrograph on the Magellan telescopes we present detailed elemental abundances for 64 red giant stars in the inner and outer Galactic disk. For the inner disk sample (4-7 kpc from…

Astrophysics of Galaxies · Physics 2012-01-11 T. Bensby , A. Alves-Brito , M. S. Oey , D. Yong , J. Meléndez

We have investigated the poorly-understood origin of nitrogen in the early Galaxy by determining N abundances in 35 extremely metal-poor halo giants (22 stars have [Fe/H]<-3.0) using the C and O abundances determined in Paper V. Because any…

Based on high-resolution spectra obtained during gravitational microlensing events we present a detailed elemental abundance analysis of 32 dwarf and subgiant stars in the Galactic bulge. [ABRIDGED], we now have 58 microlensed bulge dwarfs…

An important step in understanding the formation and evolution of the Nuclear Star Cluster (NSC) is to investigate its chemistry and chemical evolution. Additionally, exploring the relationship of the NSC to the other structures in the…

Astrophysics of Galaxies · Physics 2025-02-26 Govind Nandakumar , Nils Ryde , Mathias Schultheis , R. Michael Rich , Paola Di Matteo , Brian Thorsbro , Gregory Mace

We measure chemical abundance ratios and radial velocities in four massive (i.e., young) [alpha/Fe]-rich red giant stars using high-resolution high-S/N spectra from ESPaDOnS fed by Gemini-GRACES. Our differential analysis ensures that our…

We report the abundance analysis of one red giant branch star in the metal-poor outer halo globular cluster NGC 5694. We obtain [Fe/H] = -1.93, based on the ionized lines, and our metallicity measurement is in good agreement with previous…

Astrophysics · Physics 2009-11-11 Jae-Woo Lee , Mercedes Lopez-Morales , Bruce W. Carney

Neutral fluorine (F I) lines are identified in the optical spectra of cool EHe stars. These are the first identification of F I lines in a star's spectrum, and provide the first measurement of fluorine abundances in EHe stars. The results…

Astrophysics · Physics 2011-02-11 Gajendra Pandey

We have studied 23 long-lived G dwarfs that belong to the thin disk and thick disk stellar populations. Abundances have been derived for 24 elements: O, Na, Mg, Al, Si, Ca, Ti, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd,…

Astrophysics · Physics 2008-11-26 Mary-Margaret Brewer , Bruce W. Carney

We study the origin of iron and alpha-elements (O, Mg, Si) in clusters of galaxies. In particular, we discuss the [O/Fe] ratio and the iron mass-to-luminosity ratio in the intracluster medium (ICM) and their link to the chemical and…

Astrophysics · Physics 2016-08-30 Francesca Matteucci , Brad K. Gibson

The hot intra-cluster medium (ICM) is rich in metals, which are synthesized by supernovae (SNe) explosions and accumulate over time into the deep gravitational potential well of clusters of galaxies. Since most of the elements visible in…

Astrophysics of Galaxies · Physics 2016-08-24 François Mernier , Jelle de Plaa , Ciro Pinto , Jelle S. Kaastra , Peter Kosec , Yu-Ying Zhang , Junjie Mao , Norbert Werner

Dwarf irregular galaxies appear to have undergone very slow chemical evolution since they have low nebular abundances, but have had ongoing star formation over the past 15 Gyr. They are too distant for red giant abundance analyses to…

Astrophysics · Physics 2007-05-23 Kim Venn , Eline Tolstoy , Andreas Kaufer , Rolf Peter Kudritzki

Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations of stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been…

Growing interests in the chemical feature of r-process elements among nearby disk stars represented by the [Eu/Fe] vs. [Fe/H] diagram have sprouted since it can assess the origin of r-process elements through the comparison with theoretical…

Astrophysics of Galaxies · Physics 2019-06-26 Takuji Tsujimoto , Junichi Baba

New information on the relations between the Galactic disks, the halo, and satellite galaxies is being obtained from elemental abundances of stars having metallicities in the range -1.5 < [Fe/H] < -0.5. The first results for a sample of 26…

Astrophysics · Physics 2015-05-13 Poul E. Nissen , William J. Schuster

Asymptotic giant branch (AGB) stars are considered to be among the most significant contributors to the fluorine budget in our Galaxy. While at close-to-solar metallicity observations and theory agree, at lower metallicities stellar models…

Solar and Stellar Astrophysics · Physics 2021-08-18 D. Vescovi , S. Cristallo , S. Palmerini , C. Abia , M. Busso

Context. Recent observations of the Bulge, e.g., its X-shape, cylindrical stellar motions, and a potential fraction of young stars propose that it formed through secular evolution of the disk and not through gas dissipation and/or mergers,…

Astrophysics of Galaxies · Physics 2019-05-29 M. Lomaeva , H. Jönsson , N. Ryde , M. Schultheis , B. Thorsbro

A reanalysis of the fluorine abundance in three Galactic AGB carbon stars (TX Psc, AQ Sgr and R Scl) has been performed from the molecular HF (1-0) R9 line at 2.3358 $\mu$m. High-resolution (R$\sim 50000$) and high signal to noise spectra…

Astrophysics · Physics 2011-02-11 C. Abia , A. Recio-Blanco , P. de Laverny , S. Cristallo , I. Dominguez , O. Straniero
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