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Related papers: On the neutron-capture elements across the Galacti…

200 papers

We present a detailed analysis of the composition and nucleosynthetic origins of the heavy elements in the metal-poor ([Fe/H]=-1.62+/-0.09) star HD94028. Previous studies revealed that this star is mildly enhanced in elements produced by…

Solar and Stellar Astrophysics · Physics 2016-04-20 Ian U. Roederer , Amanda I. Karakas , Marco Pignatari , Falk Herwig

Palladium is one of poorly observed neutron-capture elements. Abundance determinations for stellar samples covering a broad metallicity range are needed for better understanding the mechanisms of Pd synthesis during the Galaxy evolution. We…

Solar and Stellar Astrophysics · Physics 2025-11-26 L. Mashonkina , A. Smogorzhevskii

We analyse all potential combinations of Galactic Cepheids and open clusters (OCs) in the most up-to-date catalogues available. Isochrone fitting and proper-motion calcula- tion are applied to all potential OC{Cepheid combinations. Five…

Astrophysics of Galaxies · Physics 2015-06-23 Xiaodian Chen , Richard de Grijs , Licai Deng

Metallicity gradients refer to the sloped radial profile of metallicities of gas and stars and are commonly seen in disk galaxies. A well-defined metallicity gradient of the Galactic disk is observed particularly well with classical…

We have derived element abundances in 310 emission-line galaxies from the Early Data Release of the Sloan Digital Sky Survey (SDSS) for which the [O {\sc iii}] 4363 emission line was detected, allowing abundance determination by direct…

Astrophysics · Physics 2009-11-10 Y. I. Izotov , G. Stasinska , N. G. Guseva , T. X. Thuan

Stellar parameters and abundances provide crucial insights into stellar and Galactic evolution studies. In this work, we developed a convolutional neural network (CNN) to estimate stellar parameters: effective temperature…

Astrophysics of Galaxies · Physics 2025-06-23 Haoyang Liu , Cuihua Du , Mingji Deng , Jian Zhang

We present gas-phase abundances of carbon (C), $\alpha$-elements (O, Ne, Si, and Ar) and iron (Fe) obtained from stacked spectra of high-$z$ star-forming galaxies with the deep Near Infrared Spectrograph medium-resolution data from the…

Neutral Fe lines in metal-poor stars yield conflicting abundances depending on whether and how deviations from local thermodynamic equilibrium (LTE) are considered. We have collected new high resolution and high signal-to-noise ultraviolet…

Solar and Stellar Astrophysics · Physics 2018-07-04 Ian U. Roederer , Christopher Sneden , James E. Lawler , Jennifer S. Sobeck , John J. Cowan , Ann Merchant Boesgaard

High-resolution spectra obtained with three ground-based facilities and the Hubble Space Telescope (HST) have been combined to produce a new abundance analysis of CS 22892-052, an extremely metal-poor giant with large relative enhancements…

Stars presently identified in the bulge spheroid are probably very old, and their abundances can be interpreted as due to the fast chemical enrichment of the early Galactic bulge. The abundances of the iron-peak elements are important…

Elemental abundance measurements have been obtained for a sample of 18 very metal-poor stars using spectra obtained with the Subaru Telescope High Dispersion Spectrograph. Seventeen stars, among which 16 are newly analyzed in the present…

We present the distributions of elemental abundance ratios using chemodynamical simulations which include four different neutron capture processes: magneto-rotational supernovae, neutron star mergers, neutrino driven winds, and electron…

Astrophysics of Galaxies · Physics 2018-12-19 Christopher Haynes , Chiaki Kobayashi

The heavy elements formed by neutron capture processes have an interesting history from which we can extract useful clues to and constraints upon both the characteristics of the processes themselves and the star formation and…

Astrophysics · Physics 2009-11-07 J. W. Truran , J. J. Cowan , C. A. Pilachowski , C. Sneden

Elements heavier than the iron group are found in nearly all halo stars. A substantial number of these elements, key to understanding neutron-capture nucleosynthesis mechanisms, can only be detected in the near-ultraviolet. We report the…

We present models for the slow neutron-capture process (s process) in asymptotic giant branch (AGB) stars of metallicity [Fe/H]=-2.3 and masses 0.9 Msun to 6 Msun. We encountered different regimes of neutron-capture nucleosynthesis…

Solar and Stellar Astrophysics · Physics 2015-06-03 Maria Lugaro , Amanda I. Karakas , Richard J. Stancliffe , Carlos Rijs

As a continuation of our previous work, which concerned the radial abundance distribution in the galactic disc over the distances 4-10 kpc this paper presents the first results on the metallicicty in the outer disc (RG > 10 kpc). Based on…

We present near-infrared spectra of ten planetary nebulae (PNe) in the Large and Small Magellanic Clouds (LMC and SMC), acquired with the FIRE and GNIRS spectrometers on the 6.5-m Baade and 8.1-m Gemini South Telescopes, respectively. We…

Solar and Stellar Astrophysics · Physics 2016-11-15 A. L. Mashburn , N. C. Sterling , S. Madonna , H. L. Dinerstein , I. U. Roederer , T. Geballe

Abundance observations indicate the presence of rapid-neutron capture (i.e., r-process) elements in old Galactic halo and globular cluster stars. Recent observations of the r-process-enriched star BD +17 3248 include new abundance…

Solar and Stellar Astrophysics · Physics 2011-06-07 John J. Cowan , Ian U. Roederer , Christopher Sneden , James E. Lawler

Aims. In this work, we aim to make a differential comparison of the neutron-capture and p-process element molybdenum (Mo) in the stellar populations in the local disk(s) and the bulge, focusing on minimising possible systematic effects in…

Solar and Stellar Astrophysics · Physics 2022-10-26 Rebecca Forsberg , Nils Ryde , Henrik Jönsson , R Michael Rich , Anders Johansen

The rapid neutron-capture ($r$-process) element europium (Eu) is a valuable tracer of neutron star mergers and other rare nucleosynthetic events. The stellar spectroscopic survey GALAH's unique wavelength range and setup include the Eu…

Astrophysics of Galaxies · Physics 2025-12-03 Sarah G. Kane , Zofia Kaczmarek , Andrew Garner , Sven Buder , Stephanie Monty , Elana Kane