![]() We analyze the resulting 3D velocities and accelerations with respect to expected motions resulting from models of the mass distribution in the GC.Ībridged: We estimate the distances to ~48 million stars detected by the By exploring the synergies of this cross-match together with Gaia parallaxes and extinction maps, the local ($d < 2$ kpc) AGB stars can be characterized. In this study, the BAaDE targets have been cross-matched with IR (2MASS) and optical Gaia samples. In order to use the BAaDE sample for kinematic studies, the stellar population should be characterized. This provides a sample of evolved stars that can be used to study the inner, optically obscured Galaxy using line of sight velocities and possibly VLBI proper motions. Currently, the Bulge Asymmetries and Dynamical Evolution (BAaDE) project is surveying infrared (IR) color-selected targets for SiO masers. ![]() ![]() Radio campaigns using maser stellar beacons have provided crucial information to characterize Galactic stellar populations. We find only marginal evidence that the mass-loss rate increases with stellar mass. The results suggest that for the mass-loss rate increases exponentially with time. By using a model-dependent transformation between the colour and mass-loss rate,, we constrain the time dependence of. We estimate the - colour distribution of AGB stars for an unbiased volume-limited sample. The overall normalization implies that there are ∼200 000 AGB stars in the Galaxy. This fall-off extends to at least 12 kpc, where the sample becomes too small. In the radial direction the number density of AGB stars is constant up to R∼ 5 kpc, and then it decreases exponentially with a scalelength of ∼1.6 kpc. Perpendicular to the Galactic plane, the number density of AGB stars is well described by an exponential function with a vertical scaleheight of 300 pc. The direct determination of this distribution shows that it is separable in the radial, R, and vertical, z, directions. We find that there are no statistically significant differences in the Galactic distribution of AGB stars with different IRAS colours, implying a universal density distribution. Assuming a bulge distance of 8 kpc, we determine LAGB∼ 3500 L⊙, in close agreement with values obtained for nearby AGB stars using the Hipparcos data, and those obtained by other methods. The characteristic AGB star luminosity, LAGB, is determined from the condition that the highest number density must coincide with the Galactic bulge. The distance to each star is estimated by assuming a narrow luminosity function and a model-derived bolometric correction. 2016).We study the Galactic distribution of ∼10 000 candidate asymptotic giant branch (AGB) stars selected by IRAS colours and variability index. 2014), and the Dark Energy Spectroscopic Instrument (DESI, DESI Collaboration et al. 2014), the Subaru Prime Focus Spectrograph (PFS, Takada et al. 2014), the Multi-Object Spectrograph for the VLT (MOONS, Cirasuolo et al. ![]() 2012), the Maunakea Spectroscopic Explorer (MSE, Simons et al. 2019) and Pitt-Google 2 are being developed to provide a fast and reliable filtering and classification to enable the real-time characterization of objects in the stream using the available follow-up resources, including massively multi-plexed spectroscopic instruments such as the 4-metre Multi-Object Spectroscopic Telescope (4MOST, de Jong et al. 2019) the Arizona-NOAO Temporal Analysis and Response to Events System (ANTARES, Narayan et al. 2021) the Alert Management, Photometry and Evaluation of Lightcurves (AMPEL, Nordin et al. Consequently, a new generation of astronomical alert brokers: the Automatic Learning for the Rapid Classification of Alerts (ALeRCE, Förster et al. These changes are reported in massive alert streams, where alerts contain image cutouts and other relevant information about objects of Solar System, Galactic, or extragalactic origin, but whose nature is not necessarily known in advance.
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