ARCS: The Asiago Red Clump Spectroscopic Survey and its First Applications

The PhD thesis "ARCS" the Asiago Red Clump Survey and its first applications" is based on the study and the use of Red Clump stars, utilizing the data from ARCS and RAVE surveys. The high luminosity, constant absolute magnitude and abundance, make Red Clump stars a powerful distance indicator and, consequently, they are an important tool for ever astrophysical question in which distance problem is relevant. ARCSs (the Asiago Red Clump Spectroscopic survey) derives from high resolution optical spectra, accurate multi-epoch radial velocities and atmospheric parameters for a well selected sample of 500 equatorial Red Clump stars (|b|<6°) , belonging to the solar neighborhood. Spectra are obtained with the Asiago 1.82m + Echelle spectrograph, they cover a wide spectral interval (3700-7300 Å) with a high resolution (R = 20,000) . Radial velocity measurements are performed by cross-correlating spectra against synthetic templates; atmospheric parameters are derived via χ2 fitting with a synthetic database of spectra. The synthetic spectra are taken from the library of Munari et al. (2005, A&A 442,1127), based on Kurucz's codes. The PhD research succeded in: -the creation of a wide catalog of RC stars; -to better investigate the structure of this type of stars; -to calibrate dependence of the absolute magnitude of RC stars against the metallicity; -to apply this function in order to define the use of RC stars as standard candles; -the use of this type of stars for analyzing Milky Way structure and kinematics.

La tesi di dottorato da titolo "ARCS: The Asiago Red Clump Survey and its firs applications" si occupa di meglio indagare e caratterizzare le stelle di Red Clump locali, al fine di utilizzare questo tipo di stelle come indicatori di distanza, struttura e cinematica della Via Lattea . Il progetto comprende la survey ARCS (Asiago Red Clump spectroscopic Survey) e si e' occupato di sfruttarne scientificamente i risultati. Parte del progetto e'stato effettuato in collaborazione con K. Freeman del Mt Stromlo Observatory. Il risultato di questo lavoro e' un esteso catalogo di parametri atmosferici e velocita' radiali per un campione di 300 stelle di Red Clump. I dati ottenuti sono stai applicati a problemi classici di struttura e cinematica galattica, come la detection di streams, la determinazione della velocità di fuga locale e presenza di dark matter.