Results 21 to 30 of about 1,884 (262)
THE IMPACT OF STELLAR ABUNDANCE VARIATIONS ON STELLAR HABITABLE ZONE EVOLUTION [PDF]
The Astrophysical Journal, 2012 The high quality spectra required for radial velocity planet searches are well-suited to providing abundances for a wide array of elements in large samples of stars. Abundance ratios of the most common elements relative to Fe are observed to vary by more than a factor of two in planet host candidates. This level of variation has a substantial impact on
Young, Patrick A. +2 more
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THE SENSITIVITY OF CONVECTION ZONE DEPTH TO STELLAR ABUNDANCES: AN ABSOLUTE STELLAR ABUNDANCE SCALE FROM ASTEROSEISMOLOGY [PDF]
The Astrophysical Journal, 2012 The base of the convection zone is a source of acoustic glitches in the asteroseismic frequency spectra of solar-like oscillators, allowing one to precisely measure the acoustic depth to the feature. We examine the sensitivity of the depth of the convection zone to mass, stellar abundances, and input physics, and in particular, the use of a measurement
van Saders, Jennifer L. +1 more
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Stellar Abundances in the Solar Neighborhood [PDF]
The Astronomical Journal, 2012 The only elements that were made in significant quantity during the Big Bang were hydrogen and helium, and to a lesser extent lithium. Depending on the initial mass of a star, it may eject some or all of the unique, newly formed elements into the interstellar medium.
Hinkel, Natalie R. +4 more
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Stellar Oxygen Abundances [PDF]
Publications of the Astronomical Society of the Pacific, 1994 This dissertation addresses several issues concerning stellar oxygen abundances. The 7774 {A} O I triplet equivalent widths of Abia & Rebolo [1989, AJ, 347, 186] for metal-poor dwarfs are found to be systematically too high. I also argue that current effective temperatures used in halo star abundance studies may be ~150 K too low.
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Abundances in Stellar Populations [PDF]
Symposium - International Astronomical Union, 1976 Stellar abundances are reviewed with emphasis on large-scale effects which may yield clues to galactic structure and evolution. Spectroscopic and indirect photoelectric abundance criteria are discussed, and utilized.The abundance statistics of nearby galactic disk stars, dominated by M dwarfs, but observed at spectral types F and GV and K III, suggest ...
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SAGA: Stellar Abundances for Galatic Archeology [PDF]
Proceedings of XII International Symposium on Nuclei in the Cosmos — PoS(NIC XII), 2013 A tutorial for the Stellar Abundances for Galactic Archaeology (SAGA) database is presented. This paper describes the outline of the database, reports the current status of the data compilation and known problems, and presents plans for future updates and extensions.
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Stellar Parameters and Chemical Abundances Estimated from LAMOST-II DR8 MRS Based on Cycle-StarNet
The Astrophysical Journal Supplement Series, 2023 Deriving stellar atmospheric parameters and chemical abundances from stellar spectra is crucial for understanding the evolution of the Milky Way. By performing a fitting with MARCS model atmospheric theoretical synthetic spectra combined with a domain ...
Rui Wang +5 more
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Stellar Abundance Observations
, 1998 10 pages, 6 figures To appear in the Proceedings of the Second Oak Ridge Symposium on Atomic & Nuclear ...
Cowan, John J +3 more
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Pediatric Blood &Cancer, EarlyView.ABSTRACT Pediatric supportive care clinical trials often involve multiple clinically important outcomes, complicating trial interpretation. Hierarchical composite endpoints (HCEs) provide a framework to integrate key outcomes according to clinical importance.
Willem H. Collier +11 more
wiley +1 more source
The Astrophysical JournalWe present a detailed chemical abundance analysis of the three brightest known stars from each of the Turranburra and Willka Yaku stellar streams using high-resolution Magellan/Magellan Inamori Kyocera Echelle spectra. Abundances for 27 elements, ranging
K. B. Webber +22 more
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