Matches in SemOpenAlex for { <https://semopenalex.org/work/W2487388961> ?p ?o ?g. }
Showing items 1 to 76 of
76
with 100 items per page.
- W2487388961 endingPage "154" @default.
- W2487388961 startingPage "154" @default.
- W2487388961 abstract "We have carried out abundance analyses of four low-mass supergiant variable stars (the RV Tauri or RV Tau-like variables AI Cmi, RU Cen, and U Mon, and the Type II Cepheid Kappa Pav) and two Population I Cepheids (CO Aur and V378 Cen). We used model atmospheres in which hydrostatic equilibrium, plane-parallel geometry, and local thermodynamic equilibrium (LTE) were assumed. Discussion of the results, and of published analyses of additional low-mass variables, leads to the following conclusions. (1) The Population I Cepheids show normal, solar elemental abundance ratios (except for the CNO elements, which have been altered by hydrogen burning), lending some support to the validity of the above assumptions for analyses of luminous variable stars. (2) The low-mass variables show metallicities ranging from solar down to [Fe/H] values typical of thick-disk and, in a few cases, of halo stars. (3) Most low-mass variables show a systematic underabundance of the heavy s- and r-process elements. In a few cases this may indicate that the stars were initially of extremely low metal content, and are now hydrogen deficient. However, most of the variables do not appear to belong to the halo population, nor do they show other abundance patterns seen in halo stars. The origin of these underabundances, and their apparent confinement to luminous variables, are difficult to understand in the context of nuclear processing. (4) The heavy-element underabundances correlate with second ionization potential in a manner suggesting that they are non-LTE phenomenan arising from overionization by Lyman-continuum photons. Why a similar effect is not seen in Population I Cepheids is unclear, but may be related to their generally weaker hydrogen emission. (5) Several low-mass variables, including RU Cen and V553 Cen, show carbon enhancements and solar s-process abundances. Relative to the majority of the Type II variables, these stars are s-process enhanced, and we argue that they are related to the Ba II and CH stars." @default.
- W2487388961 created "2016-08-23" @default.
- W2487388961 creator A5013047385 @default.
- W2487388961 creator A5034294714 @default.
- W2487388961 date "1989-01-01" @default.
- W2487388961 modified "2023-09-26" @default.
- W2487388961 title "S-Process Deficiencies in Low-Mass Supergiant Variables" @default.
- W2487388961 doi "https://doi.org/10.1017/s0252921100062849" @default.
- W2487388961 hasPublicationYear "1989" @default.
- W2487388961 type Work @default.
- W2487388961 sameAs 2487388961 @default.
- W2487388961 citedByCount "0" @default.
- W2487388961 crossrefType "journal-article" @default.
- W2487388961 hasAuthorship W2487388961A5013047385 @default.
- W2487388961 hasAuthorship W2487388961A5034294714 @default.
- W2487388961 hasBestOaLocation W24873889611 @default.
- W2487388961 hasConcept C121332964 @default.
- W2487388961 hasConcept C1276947 @default.
- W2487388961 hasConcept C144024400 @default.
- W2487388961 hasConcept C149923435 @default.
- W2487388961 hasConcept C150739758 @default.
- W2487388961 hasConcept C150846664 @default.
- W2487388961 hasConcept C151730666 @default.
- W2487388961 hasConcept C17352008 @default.
- W2487388961 hasConcept C178075534 @default.
- W2487388961 hasConcept C184665706 @default.
- W2487388961 hasConcept C198785896 @default.
- W2487388961 hasConcept C2779343474 @default.
- W2487388961 hasConcept C2908647359 @default.
- W2487388961 hasConcept C44870925 @default.
- W2487388961 hasConcept C505870484 @default.
- W2487388961 hasConcept C68944897 @default.
- W2487388961 hasConcept C77077793 @default.
- W2487388961 hasConcept C86803240 @default.
- W2487388961 hasConcept C98444146 @default.
- W2487388961 hasConcept C99465377 @default.
- W2487388961 hasConceptScore W2487388961C121332964 @default.
- W2487388961 hasConceptScore W2487388961C1276947 @default.
- W2487388961 hasConceptScore W2487388961C144024400 @default.
- W2487388961 hasConceptScore W2487388961C149923435 @default.
- W2487388961 hasConceptScore W2487388961C150739758 @default.
- W2487388961 hasConceptScore W2487388961C150846664 @default.
- W2487388961 hasConceptScore W2487388961C151730666 @default.
- W2487388961 hasConceptScore W2487388961C17352008 @default.
- W2487388961 hasConceptScore W2487388961C178075534 @default.
- W2487388961 hasConceptScore W2487388961C184665706 @default.
- W2487388961 hasConceptScore W2487388961C198785896 @default.
- W2487388961 hasConceptScore W2487388961C2779343474 @default.
- W2487388961 hasConceptScore W2487388961C2908647359 @default.
- W2487388961 hasConceptScore W2487388961C44870925 @default.
- W2487388961 hasConceptScore W2487388961C505870484 @default.
- W2487388961 hasConceptScore W2487388961C68944897 @default.
- W2487388961 hasConceptScore W2487388961C77077793 @default.
- W2487388961 hasConceptScore W2487388961C86803240 @default.
- W2487388961 hasConceptScore W2487388961C98444146 @default.
- W2487388961 hasConceptScore W2487388961C99465377 @default.
- W2487388961 hasLocation W24873889611 @default.
- W2487388961 hasOpenAccess W2487388961 @default.
- W2487388961 hasPrimaryLocation W24873889611 @default.
- W2487388961 hasRelatedWork W1513218793 @default.
- W2487388961 hasRelatedWork W1611643988 @default.
- W2487388961 hasRelatedWork W2032816401 @default.
- W2487388961 hasRelatedWork W2041813444 @default.
- W2487388961 hasRelatedWork W2098299526 @default.
- W2487388961 hasRelatedWork W3098566509 @default.
- W2487388961 hasRelatedWork W3099743823 @default.
- W2487388961 hasRelatedWork W3101204453 @default.
- W2487388961 hasRelatedWork W4300303018 @default.
- W2487388961 hasRelatedWork W84207955 @default.
- W2487388961 hasVolume "106" @default.
- W2487388961 isParatext "false" @default.
- W2487388961 isRetracted "false" @default.
- W2487388961 magId "2487388961" @default.
- W2487388961 workType "article" @default.