Results 81 to 90 of about 1,424,303 (245)

Evidence of Third Dredge-up in Post-AGB Stars in Galactic Globular Clusters

The Astrophysical Journal
To better understand the mixing and mass loss experienced by low-mass stars as they ascend the asymptotic giant branch (AGB), I have gathered from the literature the abundances of CNO and s -process elements in post-AGB stars in Galactic globular ...
William V. Dixon
doaj   +1 more source

CLEAR EVIDENCE FOR THE PRESENCE OF SECOND-GENERATION ASYMPTOTIC GIANT BRANCH STARS IN METAL-POOR GALACTIC GLOBULAR CLUSTERS [PDF]

, 2015
Galactic globular clusters (GCs) are known to host multiple stellar populations: a first generation (FG) with a chemical pattern typical of halo field stars and a second generation (SG) enriched in Na and Al and depleted in O and Mg.
D. A. García-Hernández, S. Mészáros, M. Monelli, S. Cassisi, P. Stetson, O. Zamora, M. Shetrone, S. Lucatello   +7 more
semanticscholar   +1 more source

A Solar‐like Cycle in Asymptotic Giant Branch Stars [PDF]

The Astrophysical Journal, 2000
I propose that the mechanism behind the formation of concentric semi-periodic shells found in several planetary nebulae (PNs) and proto-PNs, and around one asymptotic giant branch (AGB) star, is a solar-like magnetic activity cycle in the progenitor AGB stars.
openaire   +2 more sources

Dual‐Functional and Low‐Toxicity ZnO Nanoparticles From Pomegranate Peel: Impact of Synthesis Parameters on Photocatalytic and Supercapacitive Performance

ChemistryOpen, Volume 15, Issue 5, May 2026.
The synthesis of ZnO nanoparticles (NPs) using pomegranate peel extract at ambient temperature represents a significant advancement in the development of sustainable dual‐functional materials. These NPs demonstrated high photocatalytic efficiency in the degradation of organic pollutants and exhibited significant supercapacitive energy storage ...
Roumaissa Djafarou, Ouarda Brahmia, Naima Benchikha, Fatma Kılıç Dokan, Ertugrul Sahmetlioglu, Ayomide Victor Atoki, Mohammed Messaoudi   +6 more
wiley   +1 more source

The stellar spectral features of nearby galaxies in the near infrared: tracers of thermally pulsing asymptotic giant branch stars? [PDF]

, 2015
We analyze the stellar absorption features in high signal-to-noise ratio near-infrared (NIR) spectra of the nuclear region of 12 nearby galaxies, mostly spirals.
R. Riffel, R. Mason, L. Martins, Alberto Rodríguez-Ardila, L. Ho, R. Riffel, P. Lira, O. G. Martín, D. Ruschel-Dutra, A. Alonso-Herrero, H. Flohic, R. McDermid, C. R. Almeida, K. Thanjavur, C. Winge   +14 more
semanticscholar   +1 more source

Asymptotic Giant Branch Stars in the Magellanic Clouds [PDF]

Symposium - International Astronomical Union, 1991
Since the pioneering objective prism surveys by Westerlund (1960) and Blanco et al. (1980), the Magellanic Clouds have proved a fruitful site for exploring the evolution of AGB stars. We have used photometric techniques to extend the prism C-star surveys to M- and S-type AGB stars, constructing luminosity functions and obtaining spectra of individual ...
Neill Reid, J. R. Mould
openaire   +1 more source

Individual variability shapes interaction rewiring and fosters ecosystem restoration by reintroduced giant tortoises in the Seychelles

Restoration Ecology, Volume 34, Issue 4, May 2026.
Abstract Introduction Giant tortoises are critical for restoring lost ecological interactions on islands. Following their extinction in Seychelles centuries ago, key ecosystem processes like seed dispersal, browsing, and nutrient cycling were disrupted.
Iago Ferreiro‐Arias, Sergio García‐Peña, Christopher Kaiser‐Bunbury, Pablo Vargas   +3 more
wiley   +1 more source

First Principles Rovibronic Absorption Spectra of HF Molecule

Journal of Computational Chemistry, Volume 47, Issue 6, March 5, 2026.
Hydrogen fluoride (HF) is astrophysically important, as it has been detected in sunspots, Venus, red giants, and the interstellar medium, serving as a probe of exoplanet atmospheres. This article presents an ab initio investigation of HF rovibronic spectroscopy, combining high‐level electronic‐structure data with nuclear‐motion solutions and refinement
Nariman Abu El Kher, Maha Shibli, Mahmoud Korek, Sergei N. Yurchenko, Jonathan Tennyson, Nayla El‐Kork   +5 more
wiley   +1 more source

Li Evolution among Stars of Low/Intermediate Mass: the Metal-deficient Open Cluster NGC 2204

The Astronomical Journal
We have analyzed high-dispersion spectra in the Li 6708 Å region for 167 stars within the anticenter cluster NGC 2204. From 105 probable members, abundance analysis of 45 evolved stars produces [Fe/H] = −0.40 ± 0.12, [Si/Fe] = 0.14 ± 0.12, [Ca/Fe] = 0.29
Barbara J. Anthony-Twarog, Constantine P. Deliyannis, Aaron Steinhauer, Qinghui Sun, Bruce A. Twarog   +4 more
doaj   +1 more source

Trojan Horse Investigation for AGB Stellar Nucleosynthesis

Universe, 2022
Asymptotic Giant Branch (AGB) stars are among the most important astrophysical sites influencing the nucleosynthesis and the chemical abundances in the Universe. From a pure nuclear point of view, several processes take part during this peculiar stage of
Maria Letizia Sergi, Giuseppe D’Agata, Giovanni Luca Guardo, Giuseppe Gabriele Rapisarda, Vaclav Burjan, Silvio Cherubini, Marisa Gulino, Iolanda Indelicato, Marco La Cognata, Livio Lamia, Dario Lattuada, Jaromir Mrázek, Alessandro Alberto Oliva, Rosario Gianluca Pizzone, Stefano Romano, Roberta Spartá, Oscar Trippella, Aurora Tumino   +17 more
doaj   +1 more source