Matches in SemOpenAlex for { <https://semopenalex.org/work/W2034229231> ?p ?o ?g. }
- W2034229231 endingPage "249" @default.
- W2034229231 startingPage "234" @default.
- W2034229231 abstract "The degree of ionization, x(e) = n(e)/n(H2), and the cosmic-ray ionization rate, ζ, in 24 cloud cores have been determined by comparing observational data from Butner et al. on the abundance ratios RD = [DCO+]/[HCO+] and RH = [HCO+]/[CO] with a simple analytical chemical model and with a detailed pseudo-time-dependent chemical model. The results are dependent on the depletion of elemental carbon and oxygen from their cosmic abundances, especially for cores with a low degree of ionization. We determine the depletion of C and O from the measured HC3N/CO abundance ratios using model results. We find that the range of fractional ionization in the dark cores extends from ~10-6 to ~10-8, with inferred cosmic ray ionization rates in the range of 10-16-10-18 s-1. This corresponds to ambipolar diffusion timescales of between 3 × 107 and 3 × 105 yr, with a median value of 5 × 106 yr. The ratio of ambipolar diffusion to the free-fall timescales varies between 3 and 200, with a median value of 50. We find, rather surprisingly, no clear segregation in the ambipolar diffusion timescales between cores with embedded stars and those without. An interesting by-product of our results is the conclusion that the cyanopolyyne-rich core in TMC-1 is atypical in its abundance distribution and may be unusually young." @default.
- W2034229231 created "2016-06-24" @default.
- W2034229231 creator A5058257495 @default.
- W2034229231 creator A5060950171 @default.
- W2034229231 creator A5064768265 @default.
- W2034229231 creator A5090718980 @default.
- W2034229231 date "1998-05-20" @default.
- W2034229231 modified "2023-10-05" @default.
- W2034229231 title "The Ionization Fraction in Dense Cloud Cores" @default.
- W2034229231 cites W1652827798 @default.
- W2034229231 cites W1668005357 @default.
- W2034229231 cites W1974737886 @default.
- W2034229231 cites W1981273323 @default.
- W2034229231 cites W1990171074 @default.
- W2034229231 cites W2000108689 @default.
- W2034229231 cites W2000672249 @default.
- W2034229231 cites W2009370555 @default.
- W2034229231 cites W2009452458 @default.
- W2034229231 cites W2009654339 @default.
- W2034229231 cites W2015693937 @default.
- W2034229231 cites W2021459290 @default.
- W2034229231 cites W2024335519 @default.
- W2034229231 cites W2025462997 @default.
- W2034229231 cites W2026328109 @default.
- W2034229231 cites W2028867124 @default.
- W2034229231 cites W2030392387 @default.
- W2034229231 cites W2049707893 @default.
- W2034229231 cites W2053884662 @default.
- W2034229231 cites W2055530733 @default.
- W2034229231 cites W2063395797 @default.
- W2034229231 cites W2074365138 @default.
- W2034229231 cites W2074487737 @default.
- W2034229231 cites W2077606423 @default.
- W2034229231 cites W2085623640 @default.
- W2034229231 cites W2085956090 @default.
- W2034229231 cites W2086736601 @default.
- W2034229231 cites W2088917880 @default.
- W2034229231 cites W2091836325 @default.
- W2034229231 cites W2100758318 @default.
- W2034229231 cites W2136527880 @default.
- W2034229231 cites W2144524190 @default.
- W2034229231 cites W3110709559 @default.
- W2034229231 cites W4249176341 @default.
- W2034229231 cites W58568539 @default.
- W2034229231 doi "https://doi.org/10.1086/305624" @default.
- W2034229231 hasPublicationYear "1998" @default.
- W2034229231 type Work @default.
- W2034229231 sameAs 2034229231 @default.
- W2034229231 citedByCount "267" @default.
- W2034229231 countsByYear W20342292312012 @default.
- W2034229231 countsByYear W20342292312013 @default.
- W2034229231 countsByYear W20342292312014 @default.
- W2034229231 countsByYear W20342292312015 @default.
- W2034229231 countsByYear W20342292312016 @default.
- W2034229231 countsByYear W20342292312017 @default.
- W2034229231 countsByYear W20342292312018 @default.
- W2034229231 countsByYear W20342292312019 @default.
- W2034229231 countsByYear W20342292312020 @default.
- W2034229231 countsByYear W20342292312021 @default.
- W2034229231 countsByYear W20342292312022 @default.
- W2034229231 countsByYear W20342292312023 @default.
- W2034229231 crossrefType "journal-article" @default.
- W2034229231 hasAuthorship W2034229231A5058257495 @default.
- W2034229231 hasAuthorship W2034229231A5060950171 @default.
- W2034229231 hasAuthorship W2034229231A5064768265 @default.
- W2034229231 hasAuthorship W2034229231A5090718980 @default.
- W2034229231 hasConcept C111309251 @default.
- W2034229231 hasConcept C121332964 @default.
- W2034229231 hasConcept C145148216 @default.
- W2034229231 hasConcept C159985019 @default.
- W2034229231 hasConcept C184779094 @default.
- W2034229231 hasConcept C185544564 @default.
- W2034229231 hasConcept C192562407 @default.
- W2034229231 hasConcept C198291218 @default.
- W2034229231 hasConcept C204323151 @default.
- W2034229231 hasConcept C25621703 @default.
- W2034229231 hasConcept C44870925 @default.
- W2034229231 hasConcept C62520636 @default.
- W2034229231 hasConcept C69357855 @default.
- W2034229231 hasConcept C82706917 @default.
- W2034229231 hasConcept C97355855 @default.
- W2034229231 hasConceptScore W2034229231C111309251 @default.
- W2034229231 hasConceptScore W2034229231C121332964 @default.
- W2034229231 hasConceptScore W2034229231C145148216 @default.
- W2034229231 hasConceptScore W2034229231C159985019 @default.
- W2034229231 hasConceptScore W2034229231C184779094 @default.
- W2034229231 hasConceptScore W2034229231C185544564 @default.
- W2034229231 hasConceptScore W2034229231C192562407 @default.
- W2034229231 hasConceptScore W2034229231C198291218 @default.
- W2034229231 hasConceptScore W2034229231C204323151 @default.
- W2034229231 hasConceptScore W2034229231C25621703 @default.
- W2034229231 hasConceptScore W2034229231C44870925 @default.
- W2034229231 hasConceptScore W2034229231C62520636 @default.
- W2034229231 hasConceptScore W2034229231C69357855 @default.
- W2034229231 hasConceptScore W2034229231C82706917 @default.
- W2034229231 hasConceptScore W2034229231C97355855 @default.
- W2034229231 hasIssue "1" @default.
- W2034229231 hasLocation W20342292311 @default.