E-AGB

The strain energy (or self energy) of a dislocation actually depends on the character of the dislocation, but setting E = aGb is a good estimate, where a is -0.5. 

Nowadays it is widely accepted that the 13C(a, n)160 reaction is the main source or neutrons of the s-process in AGB stars. Comparison between the s-element abundance patterns found in AGB stars of different classes and metallicity with theoretical predictions show a nice agreement (see e.g. Busso et al. 2001 and references therein). This comparison would indicate also that, at a given stellar metallicity, a dispersion in the quantity of 13C burnt may exists as one would expect, on the other hand. In fact, s-element patterns for individual stars can be fitted assuming that the amount of 13C burnt ranges from 10 7 to almost 10-5 Mq. However, the large error bar in the abundances precludes to put more... 

An other important constraint comes from the 12C/13C ratios derived in AGB C-stars. Some discrepancy still exists among different authors concerning the typical 12C/13C ratio in these stars (see e.g. de Laverny Gustafsson 1998). However, all the authors agree in the fact that there are a significant number of... 

Recent abundance ratio work in this field falls into two categories. The first category has been investigations into aspects of metal-poor AGB and Type la SN yields and their relationship to the chemical evolution in the dSph galaxies, e.g. McWilliam et al. (2003), Venn et al. (2004), McWilliam Smecker-Hane (2005). In these works the abundances of specific elements are compared to... 

Table 6.2 gives an overview of some of the stages of stellar evolution where carbon and/or s-process anomalies occur (see Fig. 3.37). The C/O ratio increases down the series. In addition to the types listed there, there are infrared carbon stars such as IRC +10216,1 proto-planetary nebulae and a whole zoo of peculiar carbon stars, including J stars (strong 13C as in the case of HD 52432 shown in Fig. 1.7) and hydrogen-deficient carbon stars which can be cool, e.g. R Cor Bor, RY Sag and HD 137613 shown in Fig. 1.7, or hot (when they look like extreme helium stars) such stars may have lost their envelopes by binary mass transfer, or they may be born-again AGB stars. 

Lattanzio JC, Boothroyd A1 (1997) Nucleosynthesis of elements in low to intermediate mass stars through the AGB phase. In Astrophysical Implications of the Laboratory Study of Presolar Materials. Bematowicz TJ and Ziimer E (eds) AlP, New York, p 85-114... 

Effects due to solvent dielectric constant in terms of the contribution AGb (equation I) have already been considered. The destabilization effect due to a decrease in dielectric constant is relatively small as long as s S 10. On the other hand, during the complexation process the ligand binding sites have to be set free by breaking intermolecular solvent-ligand bonds. This is more difficult in polar solvents of high than for solvents of low e (5, 16). 

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