Far-Ultraviolet Radiation from Elliptical Galaxies
TLDR
In this article, it was shown that far-ultraviolet radiation is produced mainly by low-mass, small-envelope, helium-burning stars in extreme horizontal branch and subsequent phases of evolution.Abstract:
▪ Abstract Far-ultraviolet radiation is a ubiquitous, if unanticipated, phenomenon in elliptical galaxies and early-type spiral bulges. It is the most variable photometric feature associated with old stellar populations. Recent observational and theoretical evidence shows that it is produced mainly by low-mass, small-envelope, helium-burning stars in extreme horizontal branch and subsequent phases of evolution. These are probably descendants of the dominant, metal rich population of the galaxies. Their lifetime UV outputs are remarkably sensitive to their physical properties and hence to the age and the helium and metal abundances of their parents. UV spectra are therefore exceptionally promising diagnostics of old stellar populations, although their calibration requires a much improved understanding of giant branch mass loss, helium enrichment, and atmospheric diffusion.read more
Citations
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Nuclear Activity in Nearby Galaxies
TL;DR: A significant fraction of nearby galaxies show evidence of weak nuclear activity unrelated to normal stellar processes as discussed by the authors, which supports the notion that most, perhaps all, bulges host a central supermassive black hole, although the existence of active nuclei in at least some late type galaxies suggests that a classical bulge is not a prerequisite to seed a nuclear black hole.
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Nucleosynthesis in asymptotic giant branch stars: Relevance for galactic enrichment and solar system formation
TL;DR: In this paper, a review of nucleosynthesis in AGB stars outlining the development of theoretical models and their relationship to observations is presented, focusing on the new high-resolution codes with high accuracy.
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Environmental Effects on Late-Type Galaxies in Nearby Clusters
TL;DR: The transformations that take place in late-type galaxies in the environment of rich clusters of galaxies are reviewed in this paper, where the authors learn an important lesson on the latest stages of galaxy evolution, whether they were formed in situ and survived as such, avoiding transformation or even destruction, or if they are newcomers that have recently fallen in from outside.
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The GALEX Ultraviolet Atlas of Nearby Galaxies
Armando Gil de Paz,Armando Gil de Paz,Samuel Boissier,Barry F. Madore,Barry F. Madore,Mark Seibert,Y. H. Joe,Y. H. Joe,Alessandro Boselli,Ted K. Wyder,David A. Thilker,Luciana Bianchi,Soo-Chang Rey,Soo-Chang Rey,R. Michael Rich,Tom A. Barlow,Tim Conrow,Karl Forster,Peter G. Friedman,D. Christopher Martin,Patrick Morrissey,Susan G. Neff,David Schiminovich,Todd Small,Jose Donas,Timothy M. Heckman,Young-Wook Lee,Bruno Milliard,Alexander S. Szalay,Sukyoung K. Yi +29 more
TL;DR: In this article, the authors presented images, integrated photometry, and surface-brightness and color profiles for a total of 1034 nearby galaxies recently observed by the Galaxy Evolution Explorer (GALEX) satellite in its far-ultraviolet (FUV; λ_(eff) = 1516 A) and near-ult ultraviolet (NUV; Δ = 2267 A) bands.
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The propagation of uncertainties in stellar population synthesis modeling. iii. model calibration, comparison, and evaluation
Charlie Conroy,James E. Gunn +1 more
TL;DR: In this paper, a comprehensive calibration of the FSPS model against a suite of data was performed, including ultraviolet, optical, and near-IR photometry, surface brightness fluctuations, and integrated spectra of star clusters in the Magellanic Clouds (MCs), M87, M31, and the Milky Way (MW).
References
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