FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W2955874958> ?p ?o ?g. }

• W2955874958 endingPage "A36" @default.
• W2955874958 startingPage "A36" @default.
• W2955874958 abstract "Aims. Analyses of Galactic late O dwarfs (O8-O9.5V stars) raised the “weak wind problem”: spectroscopic mass-loss rates ( Ṁ ) are up to two orders of magnitude lower than the theoretical values. We investigated the stellar and wind properties of Galactic late O giants (O8-O9.5III stars). These stars have luminosities log ( L ⋆ ∕ L ⊙ ) ~ 5.2, which is the critical value (onset of weak winds) proposed in the literature. Methods. We performed a spectroscopic analysis of nine O8-O9.5III stars in the ultraviolet (UV) and optical regions using the model atmosphere code CMFGEN. Results. Stellar luminosities were adopted using calibrations from the literature. Overall, our model spectral energy distributions agree well with the observed ones considering parallaxes from the latest Gaia data release (DR2). The effective temperature derived from the UV region agrees well with the ones from the optical. As expected, the analysis of the Hertzsprung–Russell (HR) diagram shows that our sample is more evolved than late O dwarfs. From the UV region, we found Ṁ ~ 10 −8 − 10 −9 M ⊙ yr −1 overall. This is lower by ~0.9 − 2.3 dex than predicted values based on the (global) conservation of energy in the wind. The mass-loss rates predicted from first principles, based on the moving reversing layer theory, agree better with our findings, but it fails to match the spectroscopic Ṁ for the most luminous OB stars. The region of log ( L ⋆ ∕ L ⊙ ) ~ 5.2 is critical for both sets of predictions in comparison with the spectroscopic mass-loss rates. CMFGEN models with the predicted Ṁ (the former one) fail to reproduce the UV wind lines for all the stars of our sample. We reproduce the observed H α profiles of four objects with our Ṁ derived from the UV. Hence, low Ṁ values (weak winds) are favored to fit the observations (UV + optical), but discrepancies between the UV and H α diagnostics remain for some objects. Conclusions. Our results indicate weak winds beyond the O8-9.5V class, since the region of log ( L ⋆ ∕ L ⊙ ) ~ 5.2 is indeed critical to the weak wind phenomenon. Since O8-O9.5III stars are more evolved than O8-9.5V, evolutionary effects do not seem to play a role in the onset of the weak wind phenomenon. These findings support that the Ṁ (for low luminosity O stars) in use in the majority of modern stellar evolution codes must be severely overestimated up to the end of the H-burning phase. Further investigations must evaluate the consequences of weak winds in terms of physical parameters for massive stars (e.g., angular momentum and CNO surface abundances)." @default.
• W2955874958 created "2019-07-12" @default.
• W2955874958 creator A5044557883 @default.
• W2955874958 creator A5051765625 @default.
• W2955874958 creator A5059135696 @default.
• W2955874958 creator A5076394524 @default.
• W2955874958 date "2019-08-01" @default.
• W2955874958 modified "2023-10-12" @default.
• W2955874958 title "Probing the weak wind phenomenon in Galactic O-type giants" @default.
• W2955874958 cites W147232447 @default.
• W2955874958 cites W1514092272 @default.
• W2955874958 cites W1967156117 @default.
• W2955874958 cites W1983806448 @default.
• W2955874958 cites W1985422339 @default.
• W2955874958 cites W1986287522 @default.
• W2955874958 cites W2011281060 @default.
• W2955874958 cites W2016746689 @default.
• W2955874958 cites W2018337965 @default.
• W2955874958 cites W2020644470 @default.
• W2955874958 cites W2024160673 @default.
• W2955874958 cites W2024909325 @default.
• W2955874958 cites W2025107042 @default.
• W2955874958 cites W2034339735 @default.
• W2955874958 cites W2034573007 @default.
• W2955874958 cites W2037978278 @default.
• W2955874958 cites W2041169966 @default.
• W2955874958 cites W2046712375 @default.
• W2955874958 cites W2051533088 @default.
• W2955874958 cites W2051797918 @default.
• W2955874958 cites W2053646983 @default.
• W2955874958 cites W2057310326 @default.
• W2955874958 cites W2076151967 @default.
• W2955874958 cites W2088038999 @default.
• W2955874958 cites W2090455639 @default.
• W2955874958 cites W2099442838 @default.
• W2955874958 cites W2102521257 @default.
• W2955874958 cites W2112506944 @default.
• W2955874958 cites W2114246636 @default.
• W2955874958 cites W2118114070 @default.
• W2955874958 cites W2124042721 @default.
• W2955874958 cites W2128531758 @default.
• W2955874958 cites W2133725650 @default.
• W2955874958 cites W2142315862 @default.
• W2955874958 cites W2167635287 @default.
• W2955874958 cites W2259125067 @default.
• W2955874958 cites W2266202083 @default.
• W2955874958 cites W2494808941 @default.
• W2955874958 cites W2540128138 @default.
• W2955874958 cites W2550585128 @default.
• W2955874958 cites W2750666898 @default.
• W2955874958 cites W2777799209 @default.
• W2955874958 cites W2798336535 @default.
• W2955874958 cites W2903862576 @default.
• W2955874958 cites W3098560850 @default.
• W2955874958 cites W3098594318 @default.
• W2955874958 cites W3098652827 @default.
• W2955874958 cites W3098844026 @default.
• W2955874958 cites W3098851892 @default.
• W2955874958 cites W3099375806 @default.
• W2955874958 cites W3099789791 @default.
• W2955874958 cites W3100929627 @default.
• W2955874958 cites W3101187304 @default.
• W2955874958 cites W3101280497 @default.
• W2955874958 cites W3101898315 @default.
• W2955874958 cites W3102108197 @default.
• W2955874958 cites W3102957705 @default.
• W2955874958 cites W3103144565 @default.
• W2955874958 cites W3104027051 @default.
• W2955874958 cites W3104502759 @default.
• W2955874958 cites W3104704489 @default.
• W2955874958 cites W3105647200 @default.
• W2955874958 cites W3106315727 @default.
• W2955874958 cites W3122339579 @default.
• W2955874958 cites W3123670713 @default.
• W2955874958 cites W4289254994 @default.
• W2955874958 cites W4289310652 @default.
• W2955874958 cites W4292508300 @default.
• W2955874958 cites W4293717738 @default.
• W2955874958 cites W4295974042 @default.
• W2955874958 cites W4296509928 @default.
• W2955874958 cites W4298874107 @default.
• W2955874958 cites W4300351188 @default.
• W2955874958 cites W4303098660 @default.
• W2955874958 doi "https://doi.org/10.1051/0004-6361/201834266" @default.
• W2955874958 hasPublicationYear "2019" @default.
• W2955874958 type Work @default.
• W2955874958 sameAs 2955874958 @default.
• W2955874958 citedByCount "16" @default.
• W2955874958 countsByYear W29558749582020 @default.
• W2955874958 countsByYear W29558749582021 @default.
• W2955874958 countsByYear W29558749582022 @default.
• W2955874958 countsByYear W29558749582023 @default.
• W2955874958 crossrefType "journal-article" @default.
• W2955874958 hasAuthorship W2955874958A5044557883 @default.
• W2955874958 hasAuthorship W2955874958A5051765625 @default.
• W2955874958 hasAuthorship W2955874958A5059135696 @default.
• W2955874958 hasAuthorship W2955874958A5076394524 @default.
• W2955874958 hasBestOaLocation W29558749581 @default.

• next