English
Related papers

Related papers: Modal abundances of CAIs: Implications for bulk ch…

200 papers

We conducted a long-slit spectrophotometry analysis to obtain the chemical abundances of seven metal-poor HII regions in three galaxies: UM 160, UM 420, and TOL 0513-393. The data have been taken with the Focal Reducer Low Dispersion…

Astrophysics of Galaxies · Physics 2021-05-27 Mabel Valerdi , Antonio Peimbert , Manuel Peimbert

A central drop of ICM Fe abundance has been observed in several cool-core clusters. It has been proposed that this abundance drop may be due, at least partially, to the depletion of Fe into dust grains in the central, high-density regions.…

Astrophysics of Galaxies · Physics 2019-04-11 Ang Liu , Meng Zhai , Paolo Tozzi

Studies of gas-phase radial metallicity profiles in spirals published in the last decade have diminished the importance of galactic bars as agents that mix and flatten the profiles, contradicting results obtained in the 1990s. We have…

Astrophysics of Galaxies · Physics 2020-12-02 A. Zurita , E. Florido , F. Bresolin , E. Pérez-Montero , I. Pérez

Context: Chemical element abundances for distant Galactic globular clusters (GCs) hold important clues to the origin of the Milky Way halo and its substructures. Aims: We study the chemical composition of red giant stars in Pal 4 - one of…

Astrophysics of Galaxies · Physics 2015-05-18 Andreas Koch , Patrick Côté

We have determined carbon abundances or upper limits from the forbidden [C I] line at 8727.13 A for 85 F and early G type main sequence stars, with metallicities ranging between [Fe/H] = -1.0 and [Fe/H] = +0.25. The [C I] line has not been…

Astrophysics · Physics 2007-05-23 Helena Andersson , Bengt Edvardsson

Associated absorption lines (AALs) in quasar spectra are valuable probes of the gas kinematics and physical conditions in quasar environments. The host galaxies are by definition in an active evolution stage that might involve large-scale…

Astrophysics of Galaxies · Physics 2018-09-17 Chen Chen , Fred Hamann , Leah Simon , Thomas Barlow

Some families of carbonaceous chondrites are rich in prebiotic organics that may have contributed to the origin of life on Earth and elsewhere. However, the formation and chemical evolution of complex soluble organic molecules from…

Earth and Planetary Astrophysics · Physics 2023-01-12 Danna Qasim , Hannah L. McLain , Jose C. Aponte , Daniel P. Glavin , Jason P. Dworkin , Christopher K. Materese

Galactic open clusters have been long recognized as one of the best tools to investigate the chemical content of Galactic disk and its time evolution. In the last decade, many efforts have been directed to chemically characterize the old…

Solar and Stellar Astrophysics · Physics 2015-05-13 Valentina D'Orazi , Sofia Randich

The chemical abundance patterns of near-pristine objects provide important constraints on the properties of the first generations of stars in the Universe. We present the chemical abundances of five very metal-poor ([M/H]<-2.5) sub damped…

Since Gaia DR2 was released, many velocity structures in the disk have been revealed such as large scale ridge-like patterns in the phase space. Both kinematic information and stellar elemental abundances are needed to reveal their…

Astrophysics of Galaxies · Physics 2019-12-23 Xilong Liang , Jingkun Zhao , Yuqin Chen , Wenbo Zuo , Jiajun Zhang , Jia Zhu , Gang Zhao

A catalog compiling the parameters of 346 open clusters, including their metallicities, positions, ages, and velocities has been composed. The elements of the Galactic orbits for 272 of the clusters have been calculated. Spectroscopic…

Astrophysics of Galaxies · Physics 2016-02-17 V. A. Marsakov , M. L. Gozha , V. V. Koval' , L. V. Shpigel'

This work presents a uniform and homogeneous study of chemical abundances of refractory elements in 101 stars with and 94 without known planetary companions. We carry out an in-depth investigation of the abundances of Si, Ca, Sc, Ti, V, Cr,…

Astrophysics · Physics 2009-11-11 G. Gilli , G. Israelian , A. Ecuvillon , N. C. Santos , M. Mayor

Here we present results from over 500 kiloseconds Chandra and XMM-Newton observations of the cool core of the Centaurus cluster. We investigate the spatial distributions of the O, Mg, Si, S, Ar, Ca, Cr, Mn, Fe, and Ni abundances in the…

Astrophysics of Galaxies · Physics 2022-07-01 Kotaro Fukushima , Shogo B. Kobayashi , Kyoko Matsushita

XMM-Newton observations of 19 galaxy clusters are used to measure the elemental abundances and their spatial distributions in the intracluster medium. The sample mainly consists of X-ray bright and relaxed clusters with a cD galaxy. Along…

Astrophysics · Physics 2009-11-10 T. Tamura , J. S. Kaastra , J. W. A. Herder , J. A. M. Bleeker , J. R. Peterson

We present a reassessment of the radial abundance gradients of C, N, O, Ne, S, Cl and Ar in the Milky Way using deep spectra of 33 H II regions gathered from the literature, covering Galactocentric distances from 6 to 17 kpc. The distances…

Astrophysics of Galaxies · Physics 2020-06-10 Karla. Z. Arellano-Córdova , César Esteban , Jorge García-Rojas , J. Eduardo Méndez-Delgado

We present an analysis of CH band strengths in Keck LRIS spectra of a sample of 81 stars in M13 within 2 magnitudes of the main-sequence turnoff. The subgiants clearly exhibit a substantial (a factor of ~ 6) spread in [C/Fe]. Moreover, the…

Astrophysics · Physics 2009-11-07 Michael M. Briley , Judith G. Cohen , Peter B. Stetson

K- and L-type asteroids are considered to be the parent bodies of CV and CO chondrites. Spectral models of L-types invoke an enrichment in CAI with respect to the chondrites in the meteorite collection. Barbarian asteroids are associated to…

Earth and Planetary Astrophysics · Physics 2023-08-16 Max Mahlke , Jolantha Eschrig , Benoit Carry , Lydie Bonal , Pierre Beck

We present a high-precision differential abundance analysis of 16 solar-type stars in the Hyades open cluster based on high resolution, high signal-to-noise ratio (S/N ~ 350 - 400) spectra obtained from the McDonald 2.7m telescope. We…

Solar and Stellar Astrophysics · Physics 2016-03-07 F. Liu , D. Yong , M. Asplund , I. Ramirez , J. Melendez

Abundances of C, O, and Fe are determined for F and G main-sequence stars in the solar neighborhood in order to study trends and systematic differences in the C/Fe, O/Fe, and C/O ratios for stellar populations. Carbon abundances are…

Solar and Stellar Astrophysics · Physics 2014-09-05 P. E. Nissen , Y. Q. Chen , L. Carigi , W. J. Schuster , G. Zhao

We present C and O abundances in the Magellanic Clouds derived from deep spectra of HII regions. The data have been taken with the Ultraviolet-Visual Echelle Spectrograph at the 8.2-m VLT. The sample comprises 5 HII regions in the Large…

‹ Prev 1 4 5 6 7 8 10 Next ›