A cosmic abundance standard: chemical homogeneity of the solar neighbourhood and the ISM dust-phase composition Export

@article{citeulike:3453647, abstract = {A representative sample of unevolved early B-type stars in nearby OB associations and the field is analysed to unprecedented precision using NLTE techniques. The resulting chemical composition is found to be more metal-rich and much more homogeneous than indicated by previous work. A rms scatter of \~{}10\% in abundances is found for the six stars (and confirmed by six evolved stars), the same as reported for ISM gas-phase abundances. A cosmic abundance standard for the present-day solar neighbourhood is proposed, implying mass fractions for hydrogen, helium and metals of X=0.715, Y=0.271 and Z=0.014. Good agreement with solar photospheric abundances as reported from recent 3D radiative-hydrodynamical simulations of the solar atmosphere is obtained. As a first application we use the cosmic abundance standard as a proxy for the determination of the local ISM dust-phase composition, putting tight observational constraints on dust models.}, archivePrefix = {arXiv}, author = {Przybilla, Norbert and Nieva, Maria-Fernanda and Butler, Keith}, citeulike-article-id = {3453647}, citeulike-linkout-0 = {http://arxiv.org/abs/0809.2403}, citeulike-linkout-1 = {http://arxiv.org/pdf/0809.2403}, day = {24}, eprint = {0809.2403}, keywords = {chemical\_evolution, cosmic\_scatter, interstellar\_medium, solar\_neighborhood}, month = {Oct}, posted-at = {2008-10-27 16:32:28}, priority = {2}, title = {A cosmic abundance standard: chemical homogeneity of the solar neighbourhood and the ISM dust-phase composition}, url = {http://arxiv.org/abs/0809.2403}, year = {2008} }

TY - JOUR ID - citeulike:3453647 L3 - citeulike-article-id:3453647 N2 - A representative sample of unevolved early B-type stars in nearby OB associations and the field is analysed to unprecedented precision using NLTE techniques. The resulting chemical composition is found to be more metal-rich and much more homogeneous than indicated by previous work. A rms scatter of ~10% in abundances is found for the six stars (and confirmed by six evolved stars), the same as reported for ISM gas-phase abundances. A cosmic abundance standard for the present-day solar neighbourhood is proposed, implying mass fractions for hydrogen, helium and metals of X=0.715, Y=0.271 and Z=0.014. Good agreement with solar photospheric abundances as reported from recent 3D radiative-hydrodynamical simulations of the solar atmosphere is obtained. As a first application we use the cosmic abundance standard as a proxy for the determination of the local ISM dust-phase composition, putting tight observational constraints on dust models. TI - A cosmic abundance standard: chemical homogeneity of the solar neighbourhood and the ISM dust-phase composition KW - chemical_evolution KW - cosmic_scatter KW - interstellar_medium KW - solar_neighborhood AU - Przybilla, Norbert AU - Nieva, Maria-Fernanda AU - Butler, Keith PY - 2008/Oct/24/ UR - http://arxiv.org/abs/0809.2403 ER -