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Symposium 241
Symposium 241
Abstract details
TCS-CAIN Spectroscopic Follow-up: Inner structure of the Milky Way
C. Gonzalez-Fernandez, A. Cabrera-Lavers, F. Garzon, P. L. Hammersley,
M. Lopez-CorredoiraAbstract
Lately, the inner structure of the Milky Way has becomed a hot topic, specially
concerning the differenciation/presence of a bulge/bar complex. TCS-CAIN has
been a very productive effort in this field, allowing us to postulate the
presence of a long flat bar (Hammersely et al., 1994, Hammersley et al., 2000)
and a triaxial bulge (Lopez-Corredoira et al. 2000) from the examination of
infrared stellar counts obtained with the TCS (1.5m, Tenerife). Recently, these
results have been confirmed by the GLIMPSE team (Benjamin et al., 2005).
But the field is still open, since there is no celar evidence of the long bar
and the bulge being two totally diferent components or just different geometric
structures of the same entity. In an effort to clarify this point, we have
started an ambitious observational program with the TNG telescope,to obtain a
statistically significant number of low resolution (R=500) spectra; observing
the CaI, NaI and CO bandhead features (Ramirez et al., 1997) we can identify
the spectral type of the star and even further obtain a measure of its
metallicity, thus giving hints of the populations and chemical composition of
the inner parts of the Milky Way.
The final aim of this follow-up is to become a central observational program to
be acomplished with EMIR, for with its MOS features, is possible to obtain a
huge number of spectra (we aim for over 1000)with moderate resolution,
constructing a significant sample of the populations present, and hence the
properties of the structures they belong to.