TY - GEN
T1 - Solar neighbourhood and Galactic disc(s)
T2 - International Conference on Assembling the Puzzle of the Milky Way
AU - Casagrande, L.
AU - Schönrich, R.
PY - 2012
Y1 - 2012
N2 - We present a re-analysis of the Geneva-Copenhagen survey, based on improved effective temperature and metallicity scales, which also provide a better match to theoretical isochrones. The latter are used for a Bayesian investigation on stellar ages. With respect to previous analyses, our stars are on average 100 K hotter and 0.1 dex more metal rich, which shifts the peak of the metallicity distribution function around the solar value. From Strömgren photometry we are able to derive for the first time a proxy for alpha elements, which enables us to perform a tentative dissection of the chemical thin and thick disc. We find evidence for the latter being composed of an old, mildly but systematically alpha-enhanced population that extends to super solar metallicities, in agreement with spectroscopic studies. Our analysis suggests a strong interplay among ages, abundances and kinematics of stars.
AB - We present a re-analysis of the Geneva-Copenhagen survey, based on improved effective temperature and metallicity scales, which also provide a better match to theoretical isochrones. The latter are used for a Bayesian investigation on stellar ages. With respect to previous analyses, our stars are on average 100 K hotter and 0.1 dex more metal rich, which shifts the peak of the metallicity distribution function around the solar value. From Strömgren photometry we are able to derive for the first time a proxy for alpha elements, which enables us to perform a tentative dissection of the chemical thin and thick disc. We find evidence for the latter being composed of an old, mildly but systematically alpha-enhanced population that extends to super solar metallicities, in agreement with spectroscopic studies. Our analysis suggests a strong interplay among ages, abundances and kinematics of stars.
UR - http://www.scopus.com/inward/record.url?scp=84873553665&partnerID=8YFLogxK
U2 - 10.1051/epjconf/20121905004
DO - 10.1051/epjconf/20121905004
M3 - Conference contribution
SN - 9782759807185
T3 - EPJ Web of Conferences
BT - Assembling the Puzzle of the Milky Way
Y2 - 17 April 2011 through 22 April 2011
ER -