77361 : A new case of super Li - rich K giant with anomalous low 12 C / 13 C ratio
نویسنده
چکیده
Results from high resolution spectroscopic analysis of HD 77361 are reported. The LTE analysis shows that HD 77361 is a K giant of atmospheric parameters: Teff = 4580 ± 75 K, log g = 2.5 ± 0.1, and ξt = 1.40 ± 0.5 km s . We found that the atmosphere of HD 77361 is highly enriched in Li with log ǫ (Li) = 3.82 ± 0.1. With this finding the total number of super Li-rich K giants (log ǫ(Li) ≥ 3.3 ISM value) known till date reached six. Contrary to first dredge-up, extra-deep mixing and the associated cool bottom processing, and other recent predictions for K giants on the RGB luminosity bump phase, HD 77361 shows very low value of C/C = 4.3 ± 0.5 having, simultaneously, very large amount of Li. Also, HD 77361 is the only population I low luminosity (log L/L⊙ = 1.66 ± 0.1) low mass K giant (M = 1.5 ± 0.2M⊙) among the known super Li-rich K giants that has a very low C/C ratio. Results of HD 77361 further constrain our theoretical understanding of Li enhancement in the atmospheres of RGB stars. Subject headings: stars: abundances—stars: evolution— stars: late-type — stars: individual (HD 77361)
منابع مشابه
Discovery of the Most Lithium-rich Dwarf: Diffusion in Action
Using WIYN/Hydra observations, we report the first discovery of a super–Li-rich dwarf, the star J37 of the Hyades-aged cluster NGC 6633. This star’s gargantuan surface Li abundance of [ A(Li) p 4.29 0.07 A(X) { ] is a factor of 10 larger than the Li abundances observed in meteorites and in minimally depleted 12 log (N /N ) X H young open cluster stars. J37 may be the smoking gun for the action ...
متن کاملContinuous $ k $-Frames and their Dual in Hilbert Spaces
The notion of $k$-frames was recently introduced by Gu avruc ta in Hilbert spaces to study atomic systems with respect to a bounded linear operator. A continuous frame is a family of vectors in a Hilbert space which allows reproductions of arbitrary elements by continuous super positions. In this manuscript, we construct a continuous $k$-frame, so called c$k$-frame along with an atomic system ...
متن کاملThe effects of thermohaline mixing on low-metallicity asymptotic giant branch stars
We examine the effects of thermohaline mixing on the composition of the envelopes of low-metallicity asymptotic giant branch (AGB) stars. We have evolved models of 1, 1.5 and 2M from the pre-main sequence to the end of the thermally pulsing asymptotic giant branch with thermohaline mixing applied throughout the simulations. In agreement with other authors, we find that thermohaline mixing subst...
متن کاملSteam reforming of propane over Ni-K/CeO2-Al2O3 catalyst in fluidized- and fixed-bed reactors under low steam to propane ratio
Fluidized bed was employed to investigate propane steam reforming over Ni-K/CeO2-Al2O3 catalyst. The catalyst was characterized by XRD, SEM, TG/DTA, and N2 adsorption-desorption tests. Effects of promoters, space velocity, temperature, and steam/propane (S/C) ratio on propane conversion, H2 yield, H2/CO ratio, and stability were studied and discussed. The experiments were carried out under cond...
متن کاملMineral Nutrient Uptake in Cucumbers Grafted on Lagenaria siceraria and Cucurbita moschata Rootstocks in Different Temperature
An experiment was designed to investigate the effect of grafting Cucumis sativus var. Super daminos on Cucurbita moschata (Rs) and Lagenaria siceraria (Lg)which is comparing with non-grafting of Cucumis sativus var. Super daminos (Rn) and self-grafting (Rc). The experiment carried out as a factorial experiment based on complete randomized design (CRD) with 4 replicates in two temperature treatm...
متن کامل