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تسجيل مستخدم جديدRecent Results from SPLASH: Chemical Abundances and Kinematics of Andromedas Stellar Halo
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Large scale surveys of Andromedas resolved stellar populations have revolutionized our view of this galaxy over the past decade. The combination of large-scale, contiguous photometric surveys and pointed spectroscopic surveys has been particularly powerful for discovering substructure and disentangling the structural components of Andromeda. The SPLASH (Spectroscopic and Photometric Landscape of Andromedas Stellar Halo) survey consists of broad- and narrow-band imaging and spectroscopy of red giant branch stars in lines of sight ranging in distance from 2 kpc to more than 200 kpc from Andromedas center. The SPLASH data reveal a power-law surface brightness profile extending to at least two-thirds of Andromedas virial radius (Gilbert et al. 2012), a metallicity gradient extending to at least 100 kpc from Andromedas center (Gilbert et al. 2014), and evidence of a significant population of heated disk stars in Andromedas inner halo (Dorman et al. 2013). We are also using the velocity distribution of halo stars to measure the tangential motion of Andromeda (Beaton et al., in prep).
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