Bibcode
Trigo-Rodriguez, J. M.; Garcia-Hernandez, D. A.
Referencia bibliográfica
The Molecular Universe, Posters from the proceedings of the 280th Symposium of the International Astronomical Union held in Toledo, Spain, May 30-June 3, 2011, #360
Fecha de publicación:
5
2011
Número de citas
0
Número de citas referidas
0
Descripción
The origin, and role of C in the formation of first solar system
aggregates is described. Stellar grains evidence demonstrates that
Asymptotic Giant Branch (AGB) stars were nearby to the solar nebula at
the time of solar system formation. Such stars continue to burn H and He
in shells that surround the C-O core. During their evolution, flashes
occur in the He shell and the C, and O produced are eventually dredged
up into the star's envelop and then to the stellar surface, and finally
masively ejected to the interstellar medium (IM). Once in a molecular
cloud, the electrophilicity of C makes this element reactable with the
surrounding gas to produce different molecular species. Primitive
meteorites, particularly these known as chondrites, preserved primeval
materials of the disk. The abundances of short-lived radionuclides
(SLN), inferred to have been present in the early solar system (ESS),
are a constraint on the birth and early evolution of the solar system as
their relatively short half lives do not allow the observed abundances
to be explained by galactic chemical evolution processes. We present a
model of a 6.5 solar masses star of solar metallicity that
simultaneously match the abundances of SLNs inferred to have been
present in the ESS by using a dilution factor of 1 part of AGB material
per 300 parts of original solar nebula material, and taking into account
a time interval between injection of SLNs and consolidation of
chondrites equal to 0.53 Myr [2]. Such a polluting source does not
overproduce 53Mn, as supernova models do, and only marginally affects
isotopic ratios of stable elements. The AGB stars released O- and C-rich
gas with important oxidizing implications to first solar system
materials as recently detected in circumstellar environments [3]. REF:
[1] Lada C.J. and Lada E.A. 2003. Ann. Rev. A&A. 41: 57; [2]
Trigo-Rodriguez J.M. et al. 2009. MAPS 44: 627; [3] Decin L. et al.
2010. Nature 467: 64.